Power loss, getting worse by the day!
08-26-08, 07:27 PM
#1
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Power loss, getting worse by the day!
Ok, this one has me REALLY stumped.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
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As some of you know I finally got my car running and drivable last week. Since then I have driven it maybe 100 miles. In that amount of time I have noticed a significant power loss from when it was first running.<o:p></o:p>
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An example: at a stop sign near my house I used to be able to stopm on the gas after the car was fully in gear and the rear would “drift” through the turn. First time was actually by mistake it was so easy.<o:p></o:p>
<o:p></o:p>
Today I tried it and could not get it to do it no matter what.<o:p></o:p>
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Plus a lot of other things I know for a fact I have lost power. The aux ports have never worked so that is not the problem. Injectors were JUST cleaned. New fuel pump and filter (plus it doesn’t seem like a fuel issue). New air filter. New plugs. New OMP injectors and pump, also running pre-mix for good measure. You name it is most likely new.<o:p></o:p>
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The power loss seems to be getting worse is what really has me stumped. I took the car by the Rotary shop (works on RX7’s all day) and he said the engine sounds fine and appears to be running fine just be hearing and looking at it. so it is nothing major major. But what is it??<o:p></o:p>
<o:p></o:p>
He did say that my TPS could be bad/going bad. But would that cause this kind of power loss all through the power band? Also, could a degree or 2 of timing cause it? my CAS is not screwed down right now and it is possible that it has rotated some. Going to reset the timing tomorrow.<o:p></o:p>
<o:p></o:p>
One other note, I have a little 3800rpm lag again. It had gone away but it is now back, not a lot but it is there. It has me thinking, could it be an electrical issue? I have also noticed that my cars voltage is sitting at 13.8 vs the normal 14.4. <o:p></o:p>
<o:p></o:p>
So any ideas on how to get my power back? I have not even driven the car that hard since I got it running, a hand ful of redlines and WOT runs and 1 bunrout. About all the hard driving it has seen. It was also rebuilt ~10,000k – 15,000 miles ago.
<o:p></o:p>
As some of you know I finally got my car running and drivable last week. Since then I have driven it maybe 100 miles. In that amount of time I have noticed a significant power loss from when it was first running.<o:p></o:p>
<o:p></o:p>
An example: at a stop sign near my house I used to be able to stopm on the gas after the car was fully in gear and the rear would “drift” through the turn. First time was actually by mistake it was so easy.<o:p></o:p>
<o:p></o:p>
Today I tried it and could not get it to do it no matter what.<o:p></o:p>
<o:p></o:p>
Plus a lot of other things I know for a fact I have lost power. The aux ports have never worked so that is not the problem. Injectors were JUST cleaned. New fuel pump and filter (plus it doesn’t seem like a fuel issue). New air filter. New plugs. New OMP injectors and pump, also running pre-mix for good measure. You name it is most likely new.<o:p></o:p>
<o:p></o:p>
The power loss seems to be getting worse is what really has me stumped. I took the car by the Rotary shop (works on RX7’s all day) and he said the engine sounds fine and appears to be running fine just be hearing and looking at it. so it is nothing major major. But what is it??<o:p></o:p>
<o:p></o:p>
He did say that my TPS could be bad/going bad. But would that cause this kind of power loss all through the power band? Also, could a degree or 2 of timing cause it? my CAS is not screwed down right now and it is possible that it has rotated some. Going to reset the timing tomorrow.<o:p></o:p>
<o:p></o:p>
One other note, I have a little 3800rpm lag again. It had gone away but it is now back, not a lot but it is there. It has me thinking, could it be an electrical issue? I have also noticed that my cars voltage is sitting at 13.8 vs the normal 14.4. <o:p></o:p>
<o:p></o:p>
So any ideas on how to get my power back? I have not even driven the car that hard since I got it running, a hand ful of redlines and WOT runs and 1 bunrout. About all the hard driving it has seen. It was also rebuilt ~10,000k – 15,000 miles ago.
08-26-08, 11:54 PM
#4
straight from www.fc3spro.com
"Q: How do I do a compression check on my engine?
A compression check is a quick and easy method to check the condition of the internals of the rotary engine. The compression check requires a compression tester or a pressure gauge that goes up to at least 150psi.
As per Mazda standards, the compressor tester fitting is screwed into the TRAILING or TOP spark plugs position. The other trailing spark plug needs to be removed also, so it's easiest to remove both trailing spark plugs before starting the compression test. The throttle needs to be opened all the way, so you need to prop the throttle body or step on the gas pedal to WOT. Mazda specs also require the compression test be done when the engine is warmed up. Surprisingly, compression is higher when the engine is cold. Engine RPM cranking speeds should be between 200 to 250RPM.
Make sure the engine doesn't fire when doing the compression test! The easiest thing to do is pull the EGI fuses under the hood to prevent the ECU from starting the engine. Please ensure you have a strong battery or a battery charger closeby when you go through this procedure. You will be cranking the engine over several times, and this can drain even a good battery rather quickly.
If you're using a piston compression tester, you can remove the bypass valve or just hold the pin in. We will need to see three pulses for all three rotor faces for each rotor, so the check valve needs to be bypassed.
Mazda has set minimum compression pressure to be at 70psi, but with the FD3S, the number has been lowered to 60psi. Good compression are readings anything above 100psi. Compression testing under 80psi is a sign of an engine requiring a rebuild soon. Compression should be even across all three rotor faces on both the front and rear rotors. It is more important to have all even compression numbers across the rotor faces versus one really high number on one face.
Unless you're using an official Mazda compression tester, you might need to "calibrate" your (piston) compression tester. Some compression testers read a little low, so it's nice to know what is good for your tester. If you're getting lower readings than expected, test a known good engine for it's compression to make sure the readings are valid. I had a compression tester that tested my motor at around 80psi, but this was what a normally good engine would read on this particular tester."
"Q: How do I do a compression check on my engine?
A compression check is a quick and easy method to check the condition of the internals of the rotary engine. The compression check requires a compression tester or a pressure gauge that goes up to at least 150psi.
As per Mazda standards, the compressor tester fitting is screwed into the TRAILING or TOP spark plugs position. The other trailing spark plug needs to be removed also, so it's easiest to remove both trailing spark plugs before starting the compression test. The throttle needs to be opened all the way, so you need to prop the throttle body or step on the gas pedal to WOT. Mazda specs also require the compression test be done when the engine is warmed up. Surprisingly, compression is higher when the engine is cold. Engine RPM cranking speeds should be between 200 to 250RPM.
Make sure the engine doesn't fire when doing the compression test! The easiest thing to do is pull the EGI fuses under the hood to prevent the ECU from starting the engine. Please ensure you have a strong battery or a battery charger closeby when you go through this procedure. You will be cranking the engine over several times, and this can drain even a good battery rather quickly.
If you're using a piston compression tester, you can remove the bypass valve or just hold the pin in. We will need to see three pulses for all three rotor faces for each rotor, so the check valve needs to be bypassed.
Mazda has set minimum compression pressure to be at 70psi, but with the FD3S, the number has been lowered to 60psi. Good compression are readings anything above 100psi. Compression testing under 80psi is a sign of an engine requiring a rebuild soon. Compression should be even across all three rotor faces on both the front and rear rotors. It is more important to have all even compression numbers across the rotor faces versus one really high number on one face.
Unless you're using an official Mazda compression tester, you might need to "calibrate" your (piston) compression tester. Some compression testers read a little low, so it's nice to know what is good for your tester. If you're getting lower readings than expected, test a known good engine for it's compression to make sure the readings are valid. I had a compression tester that tested my motor at around 80psi, but this was what a normally good engine would read on this particular tester."
08-27-08, 02:10 AM
#5
you say its not to bad of a hesitation? how long has the car been sitting? if it has been sitting for a good amount of time your tank could have rusted wich would cause your fuel filter and fuel pump sock to begin to clog. just take out the fuel pump and see if its nastyly brown.
also timing could have alot to do with it as well as your o2 going bad along with your tps sensor maybe misadjusted or bad as well.
just some things to look over
also timing could have alot to do with it as well as your o2 going bad along with your tps sensor maybe misadjusted or bad as well.
just some things to look over
08-27-08, 10:36 AM
#6
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I remember from your other thread that the filter sock was disgusting. I realize you got a new one (and I think replaced the tank). I would check that again to make sure it is all good. Next, did you replace your fuel filter after the dirty sock incident? If not, you need to.
Does the car have a catalytic convertor? If so, It may be clogged. I had this happen on my RX8 and it was a drastic loss that occurred over about 2 weeks. Everyday it got worse, until it was undrivable!
your voltage is fine! I wouldn't worry about that.
The CAS possibly moving could cause it. Not if it is a degree or two off, but it can be several degrees off if it is moving.
Lastly, you are running pre-mix and an OMP. I remember a thread from years back that a TII engine in a plane was having similar issues. It was figured out that there was WAY too much oil in the engine. It caused power loss from lack of compression (the oil would just blow between the seals when pressurized). The oil will also cause a very hard to ignite mixture. Try not running premix for a while if all of the above is of no help.
Does the car have a catalytic convertor? If so, It may be clogged. I had this happen on my RX8 and it was a drastic loss that occurred over about 2 weeks. Everyday it got worse, until it was undrivable!
your voltage is fine! I wouldn't worry about that.
The CAS possibly moving could cause it. Not if it is a degree or two off, but it can be several degrees off if it is moving.
Lastly, you are running pre-mix and an OMP. I remember a thread from years back that a TII engine in a plane was having similar issues. It was figured out that there was WAY too much oil in the engine. It caused power loss from lack of compression (the oil would just blow between the seals when pressurized). The oil will also cause a very hard to ignite mixture. Try not running premix for a while if all of the above is of no help.
08-27-08, 11:51 AM
#7
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straight from www.fc3spro.com
"Q: How do I do a compression check on my engine?
A compression check is a quick and easy method to check the condition of the internals of the rotary engine. The compression check requires a compression tester or a pressure gauge that goes up to at least 150psi.
As per Mazda standards, the compressor tester fitting is screwed into the TRAILING or TOP spark plugs position. The other trailing spark plug needs to be removed also, so it's easiest to remove both trailing spark plugs before starting the compression test. The throttle needs to be opened all the way, so you need to prop the throttle body or step on the gas pedal to WOT. Mazda specs also require the compression test be done when the engine is warmed up. Surprisingly, compression is higher when the engine is cold. Engine RPM cranking speeds should be between 200 to 250RPM.
Make sure the engine doesn't fire when doing the compression test! The easiest thing to do is pull the EGI fuses under the hood to prevent the ECU from starting the engine. Please ensure you have a strong battery or a battery charger closeby when you go through this procedure. You will be cranking the engine over several times, and this can drain even a good battery rather quickly.
If you're using a piston compression tester, you can remove the bypass valve or just hold the pin in. We will need to see three pulses for all three rotor faces for each rotor, so the check valve needs to be bypassed.
Mazda has set minimum compression pressure to be at 70psi, but with the FD3S, the number has been lowered to 60psi. Good compression are readings anything above 100psi. Compression testing under 80psi is a sign of an engine requiring a rebuild soon. Compression should be even across all three rotor faces on both the front and rear rotors. It is more important to have all even compression numbers across the rotor faces versus one really high number on one face.
Unless you're using an official Mazda compression tester, you might need to "calibrate" your (piston) compression tester. Some compression testers read a little low, so it's nice to know what is good for your tester. If you're getting lower readings than expected, test a known good engine for it's compression to make sure the readings are valid. I had a compression tester that tested my motor at around 80psi, but this was what a normally good engine would read on this particular tester."
"Q: How do I do a compression check on my engine?
A compression check is a quick and easy method to check the condition of the internals of the rotary engine. The compression check requires a compression tester or a pressure gauge that goes up to at least 150psi.
As per Mazda standards, the compressor tester fitting is screwed into the TRAILING or TOP spark plugs position. The other trailing spark plug needs to be removed also, so it's easiest to remove both trailing spark plugs before starting the compression test. The throttle needs to be opened all the way, so you need to prop the throttle body or step on the gas pedal to WOT. Mazda specs also require the compression test be done when the engine is warmed up. Surprisingly, compression is higher when the engine is cold. Engine RPM cranking speeds should be between 200 to 250RPM.
Make sure the engine doesn't fire when doing the compression test! The easiest thing to do is pull the EGI fuses under the hood to prevent the ECU from starting the engine. Please ensure you have a strong battery or a battery charger closeby when you go through this procedure. You will be cranking the engine over several times, and this can drain even a good battery rather quickly.
If you're using a piston compression tester, you can remove the bypass valve or just hold the pin in. We will need to see three pulses for all three rotor faces for each rotor, so the check valve needs to be bypassed.
Mazda has set minimum compression pressure to be at 70psi, but with the FD3S, the number has been lowered to 60psi. Good compression are readings anything above 100psi. Compression testing under 80psi is a sign of an engine requiring a rebuild soon. Compression should be even across all three rotor faces on both the front and rear rotors. It is more important to have all even compression numbers across the rotor faces versus one really high number on one face.
Unless you're using an official Mazda compression tester, you might need to "calibrate" your (piston) compression tester. Some compression testers read a little low, so it's nice to know what is good for your tester. If you're getting lower readings than expected, test a known good engine for it's compression to make sure the readings are valid. I had a compression tester that tested my motor at around 80psi, but this was what a normally good engine would read on this particular tester."
you say its not to bad of a hesitation? how long has the car been sitting? if it has been sitting for a good amount of time your tank could have rusted wich would cause your fuel filter and fuel pump sock to begin to clog. just take out the fuel pump and see if its nastyly brown.
also timing could have alot to do with it as well as your o2 going bad along with your tps sensor maybe misadjusted or bad as well.
just some things to look over
also timing could have alot to do with it as well as your o2 going bad along with your tps sensor maybe misadjusted or bad as well.
just some things to look over
The O2 sensor is brand new (you name it, it is most likely new) TPS is set right but it is possible it is bad, when i was testing it, it seemed to now have the full rage it should have.
Timing i am going to check later today.
This is what has me so baffled, i have replaced virtually everything on the car. I don't know what could be causing this.
I remember from your other thread that the filter sock was disgusting. I realize you got a new one (and I think replaced the tank). I would check that again to make sure it is all good. Next, did you replace your fuel filter after the dirty sock incident? If not, you need to.
Does the car have a catalytic convertor? If so, It may be clogged. I had this happen on my RX8 and it was a drastic loss that occurred over about 2 weeks. Everyday it got worse, until it was undrivable!
your voltage is fine! I wouldn't worry about that.
The CAS possibly moving could cause it. Not if it is a degree or two off, but it can be several degrees off if it is moving.
Lastly, you are running pre-mix and an OMP. I remember a thread from years back that a TII engine in a plane was having similar issues. It was figured out that there was WAY too much oil in the engine. It caused power loss from lack of compression (the oil would just blow between the seals when pressurized). The oil will also cause a very hard to ignite mixture. Try not running premix for a while if all of the above is of no help.
Does the car have a catalytic convertor? If so, It may be clogged. I had this happen on my RX8 and it was a drastic loss that occurred over about 2 weeks. Everyday it got worse, until it was undrivable!
your voltage is fine! I wouldn't worry about that.
The CAS possibly moving could cause it. Not if it is a degree or two off, but it can be several degrees off if it is moving.
Lastly, you are running pre-mix and an OMP. I remember a thread from years back that a TII engine in a plane was having similar issues. It was figured out that there was WAY too much oil in the engine. It caused power loss from lack of compression (the oil would just blow between the seals when pressurized). The oil will also cause a very hard to ignite mixture. Try not running premix for a while if all of the above is of no help.
Correct, the entire fuel system is brand new. filter and hoses ncluded.
It does have a CAT, funny you should say that, the guy at the rotary shop also said it could be that. I might have someone put a stright pipe on it if nothing else works and see what that does. So yours really went bad in a matter of 2 weeks? Any idea why?
Going to checkt he CAS later today and also get a botl to lock it down with.
The reason for running pre-mix and OMP is that i was/am not 100% sure the OMP is working. I wanted to be on the safe side, and figured too much oil was far better then too little. but this is very possible.
I was looking at the engine today and i think that the OMP is working, there is some oil on the intake from one of the OMP injectors leaking (i can live with that, i ain't pulling the intake off again just for a leaking oil injector). So it is possible that ould be the problem.
If this is the case though, i would assume that the plugs will show the oil when i pull them right?
Thanks for the idea on what to look for everyone! Will report back tonight with what i find.
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08-27-08, 01:21 PM
#8
Don't get a straight pipe. You need the main cat to open the auxiliary ports. I'd just take it down to a muffler shop and see what they can do. If they are fubar you can gut the pre-cats and get a new main cat and you're good to go. Replacing all 3 is well over $300, but I have heard that you can pass smog with just the main cat, just don't take it as gospel. You can always weld some pre-cats on there later if you don't pass smog.
BTW, I had this happen in my car and replacing the pre-cats fixed all that. Too bad my excessive oil burning engine blew them up in a year.
08-27-08, 01:27 PM
#10
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They get clogged and exhaust gasses cannot escape fast enough.
Don't get a straight pipe. You need the main cat to open the auxiliary ports. I'd just take it down to a muffler shop and see what they can do. If they are fubar you can gut the pre-cats and get a new main cat and you're good to go. Replacing all 3 is well over $300, but I have heard that you can pass smog with just the main cat, just don't take it as gospel. You can always weld some pre-cats on there later if you don't pass smog.
BTW, I had this happen in my car and replacing the pre-cats fixed all that. Too bad my excessive oil burning engine blew them up in a year.
Don't get a straight pipe. You need the main cat to open the auxiliary ports. I'd just take it down to a muffler shop and see what they can do. If they are fubar you can gut the pre-cats and get a new main cat and you're good to go. Replacing all 3 is well over $300, but I have heard that you can pass smog with just the main cat, just don't take it as gospel. You can always weld some pre-cats on there later if you don't pass smog.
BTW, I had this happen in my car and replacing the pre-cats fixed all that. Too bad my excessive oil burning engine blew them up in a year.
Well my aux port already don't work so that is not a problem. And the PO already had the precats taken off and a new main cat welded on. so that is done as well. All that is there is the Main cat.
So i figure take the cat off for $20, then next year when it is time for inspection, put another one on for $75. Meanwhile know what the problem is. But really i am first going to see what i find out with the rest of the things above when i get off work. hopfully i will find the problem there.
08-27-08, 01:31 PM
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Plus it was just rebuilt about 10K ago. not saying you are wrong, just woundering why or how that could happen? Seems like if it was going to have problems it whould have been right after i got it started after sitting for 3 years, not after it has been running for a few weeks.
08-27-08, 01:45 PM
#12
Well my aux port already don't work so that is not a problem. And the PO already had the precats taken off and a new main cat welded on. so that is done as well. All that is there is the Main cat.
So i figure take the cat off for $20, then next year when it is time for inspection, put another one on for $75. Meanwhile know what the problem is. But really i am first going to see what i find out with the rest of the things above when i get off work. hopfully i will find the problem there.
So i figure take the cat off for $20, then next year when it is time for inspection, put another one on for $75. Meanwhile know what the problem is. But really i am first going to see what i find out with the rest of the things above when i get off work. hopfully i will find the problem there.
If you have access to an air compressor i'd try blowing some air into that rubber hose that goes to the auxiliary ports and see if they are working. They should move with 2 psi positive pressure so if you're putting 20 psi into it they should both snap open. If not, you have a leak somewhere, which the new gaskets would fix.
BTW, try replacing your fuel pump. If you sucked a bunch of crap into it when you ran out of gas it's probably on its way out. I'd suggest a junkyard replacement, but i've gotten dead one's from there before.
08-27-08, 02:01 PM
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It can be fixed. I went from sleeves removed and no cats to working aux ports in a few months. I'm not sure how much you know about it, but that split air pipe has to be there coming from the main cat. Also, check and make sure the aux ports themselves move freely. Take the actuators off if you have to and see if the actual ports are movable and check the actuators as well. They can get jammed up too. Just remember to replace the gaskets for the actuators if you take them off. It's $2 from the dealership for a set.
If you have access to an air compressor i'd try blowing some air into that rubber hose that goes to the auxiliary ports and see if they are working. They should move with 2 psi positive pressure so if you're putting 20 psi into it they should both snap open. If not, you have a leak somewhere, which the new gaskets would fix.
BTW, try replacing your fuel pump. If you sucked a bunch of crap into it when you ran out of gas it's probably on its way out. I'd suggest a junkyard replacement, but i've gotten dead one's from there before.
If you have access to an air compressor i'd try blowing some air into that rubber hose that goes to the auxiliary ports and see if they are working. They should move with 2 psi positive pressure so if you're putting 20 psi into it they should both snap open. If not, you have a leak somewhere, which the new gaskets would fix.
BTW, try replacing your fuel pump. If you sucked a bunch of crap into it when you ran out of gas it's probably on its way out. I'd suggest a junkyard replacement, but i've gotten dead one's from there before.
The problem now is that the actuators take too much pressure to open and don't open with jus tthe exahust pressure.
So i am going to convert them to an eletric aux ports witha pump that will open them. but right now they won't work no matter what (trust me i tired). And i am not going to spend the $$$ to get new actuators when i can just convert these to eletric.
As for the fuel pump, I guess it is possible that it is bad, though it was working fine for a Turbo car before i pulled it out. Plus it doesn't act liek afuel problem, i had the pump go out on me earlier and it was quite differnt the way it acted.
All options though.
No idea, though i assume it was, i just bought the car after it had sat for 3 years. The shop that rebuilt it and the PO would have broken it in right i am sure. all i know is that it has about 10k on the rebuild and sat for 3 years before i got it. then i got it running after a lot of work and now it is not running as good as when i first got it running.
08-27-08, 06:12 PM
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Ok, so i went out and tested things.
I now have some awnsers and more questions.
So i first looked at the CAS, and sure enough it was off. It was retarded about 1/4 of that adjustment groove.
So first i reset it to normal and took it for a drive. And guess what? The lost power was back!
Not sure if it was full power as before but it was still noticeably more power then before.
So i went ahead and decided to check the compression. I pulled the plugs, and sure enough even though they are less then 40miles old they were pretty dang dirty. lot of carbon build up from oil.
so that might also be a problem as well and might explain the numbers i got on the compression test.
I first ran the test on the rear rotor, and got 3 consistant puffs of ~60psi.
I then ran the test on the front rotor, got the same 3 puffs at just a tad higher then the rear ~65psi.
BUT i then decided to test it with the check valve hooked up.
And got some differnt numbers, about ~90psi on the rear and ~95psi on the front.
I also don't know if the gauge is right or not, very possible it could be wrong as well.
If it is really 60psi on each rotor i would think the engine would not even run much less get good power and start easy everytime.
I am thinking i might take it by the rotary shop and see if i can get him to test the compression for me with his tester.
And as said before that too much oil idea could be part of the problem.
So what do ya'll make of this?
I now have some awnsers and more questions.
So i first looked at the CAS, and sure enough it was off. It was retarded about 1/4 of that adjustment groove.
So first i reset it to normal and took it for a drive. And guess what? The lost power was back!
Not sure if it was full power as before but it was still noticeably more power then before.
So i went ahead and decided to check the compression. I pulled the plugs, and sure enough even though they are less then 40miles old they were pretty dang dirty. lot of carbon build up from oil.
so that might also be a problem as well and might explain the numbers i got on the compression test.
I first ran the test on the rear rotor, and got 3 consistant puffs of ~60psi.
I then ran the test on the front rotor, got the same 3 puffs at just a tad higher then the rear ~65psi.
BUT i then decided to test it with the check valve hooked up.
And got some differnt numbers, about ~90psi on the rear and ~95psi on the front.
I also don't know if the gauge is right or not, very possible it could be wrong as well.
If it is really 60psi on each rotor i would think the engine would not even run much less get good power and start easy everytime.
I am thinking i might take it by the rotary shop and see if i can get him to test the compression for me with his tester.
And as said before that too much oil idea could be part of the problem.
So what do ya'll make of this?
08-29-08, 10:53 AM
#16
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So no one knows why the car was getting only about 60psi compression on all 3 rotor faces with the check valve off?
Then 90psi with the check valve on?
And yet it still runs fine and gets good power to boot?
Trying to decide what is going on with this engine so i can decide what to do with this car. Anyone ever heard of this before?
Then 90psi with the check valve on?
And yet it still runs fine and gets good power to boot?
Trying to decide what is going on with this engine so i can decide what to do with this car. Anyone ever heard of this before?
08-31-08, 10:33 AM
#17
So no one knows why the car was getting only about 60psi compression on all 3 rotor faces with the check valve off?
Then 90psi with the check valve on?
And yet it still runs fine and gets good power to boot?
Trying to decide what is going on with this engine so i can decide what to do with this car. Anyone ever heard of this before?
Then 90psi with the check valve on?
And yet it still runs fine and gets good power to boot?
Trying to decide what is going on with this engine so i can decide what to do with this car. Anyone ever heard of this before?
The second test is with the check valve closed. This tests the ultimate compression. Here is where you should be concerned with the max number. 90+ is fine, your compression is ok. Not stellar, but really it is just fine. You pass the second test as well.
08-31-08, 10:38 AM
#18
I actually just got through pulling the intake off to fix the AUX ports. Got them freed up and to where they can open.
The problem now is that the actuators take too much pressure to open and don't open with jus tthe exahust pressure.
So i am going to convert them to an eletric aux ports witha pump that will open them. but right now they won't work no matter what (trust me i tired). And i am not going to spend the $$$ to get new actuators when i can just convert these to eletric.
As for the fuel pump, I guess it is possible that it is bad, though it was working fine for a Turbo car before i pulled it out. Plus it doesn't act liek afuel problem, i had the pump go out on me earlier and it was quite differnt the way it acted.
The problem now is that the actuators take too much pressure to open and don't open with jus tthe exahust pressure.
So i am going to convert them to an eletric aux ports witha pump that will open them. but right now they won't work no matter what (trust me i tired). And i am not going to spend the $$$ to get new actuators when i can just convert these to eletric.
As for the fuel pump, I guess it is possible that it is bad, though it was working fine for a Turbo car before i pulled it out. Plus it doesn't act liek afuel problem, i had the pump go out on me earlier and it was quite differnt the way it acted.
I would try cutting out the cat and replacing it with a strait pipe for testing purposes. On my S5 I used to remove my cat and run a pipe, then replace it with the cat just before testing. I used Stainless Steel band clamps from Summit Racing. This way, I didn't have to pay anyone to weld anything. Put the car up on jacks and change out the cat and pipe in about an hour.
08-31-08, 10:59 AM
#19
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Your compression is fine. There are two tests using the piston compression tester. Test one is to determine if you get three even bounces. This test is done with the check valve removed. This is to confirm that all the apex seals are intact and sealing uniformly. You pass the first test.
The second test is with the check valve closed. This tests the ultimate compression. Here is where you should be concerned with the max number. 90+ is fine, your compression is ok. Not stellar, but really it is just fine. You pass the second test as well.
The second test is with the check valve closed. This tests the ultimate compression. Here is where you should be concerned with the max number. 90+ is fine, your compression is ok. Not stellar, but really it is just fine. You pass the second test as well.
The compression may also come up a little once the extra oil from pre-mix and omp is not in there. So yeah i think it is ok. as you said not great but ok.
Here is your problem perhaps. You have a turbo pump on an n/a or maybe even a walbro? You may be running pig rich. Now we can guess that you have melted the cat with the overrich condition.
I would try cutting out the cat and replacing it with a strait pipe for testing purposes. On my S5 I used to remove my cat and run a pipe, then replace it with the cat just before testing. I used Stainless Steel band clamps from Summit Racing. This way, I didn't have to pay anyone to weld anything. Put the car up on jacks and change out the cat and pipe in about an hour.
I would try cutting out the cat and replacing it with a strait pipe for testing purposes. On my S5 I used to remove my cat and run a pipe, then replace it with the cat just before testing. I used Stainless Steel band clamps from Summit Racing. This way, I didn't have to pay anyone to weld anything. Put the car up on jacks and change out the cat and pipe in about an hour.
And this could be the problem.
I was wanting to remove the cat anyways BUT when i took it to the only shop i could find that would do it they would only weld a pipe to it, no flanges.
How do you make the cat/test pipe interchangeable without welding? Got any pictures?
That is exactly what i want to do actually.
08-31-08, 11:21 AM
#20
That kinda what i was thinking but i had searched and everyone just said to check the pressure from the bounces.
The compression may also come up a little once the extra oil from pre-mix and omp is not in there. So yeah i think it is ok. as you said not great but ok.
Well the pump was actually out of my parts car, which had an S5 turbo swap done to it before i got it. So i assume it is a turbo pump.
And this could be the problem.
I was wanting to remove the cat anyways BUT when i took it to the only shop i could find that would do it they would only weld a pipe to it, no flanges.
How do you make the cat/test pipe interchangeable without welding? Got any pictures?
That is exactly what i want to do actually.
The compression may also come up a little once the extra oil from pre-mix and omp is not in there. So yeah i think it is ok. as you said not great but ok.
Well the pump was actually out of my parts car, which had an S5 turbo swap done to it before i got it. So i assume it is a turbo pump.
And this could be the problem.
I was wanting to remove the cat anyways BUT when i took it to the only shop i could find that would do it they would only weld a pipe to it, no flanges.
How do you make the cat/test pipe interchangeable without welding? Got any pictures?
That is exactly what i want to do actually.
https://www.rx7club.com/showpost.php...65&postcount=3
I used my exhaust cuttoff tool to make an even cut about 3" or 4" from each end of the cat. I removed the cat and measured the length of the assembly. I then cut the same length less 1/8 " out of a new blank piece of exhaust piping (bought at Pep Boys). I used the Summit Clamps to clamp the pipe into place. Works like a charm.
Here is the Summit racing clamp. I used two of them, one on each end.
Check your pipe size, to make sure you get the right size clamp. They are NOT adaptable to different sizes, you have to order the correct size or it will not work.http://store.summitracing.com/partde...5&autoview=sku
Here is what I used to cut the exhaust pipe.
http://www.mactools.com/Mac/Mac+Prod.../Exhaust/MT770
I got mine at Autozone. It is not mac brand, but it works just fine. Cost maybe $25?
08-31-08, 11:34 AM
#21
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Here is my guide to compression testing. It should be archived, but it is not.
https://www.rx7club.com/showpost.php...65&postcount=3
I used my exhaust cuttoff tool to make an even cut about 3" or 4" from each end of the cat. I removed the cat and measured the length of the assembly. I then cut the same length less 1/8 " out of a new blank piece of exhaust piping (bought at Pep Boys). I used the Summit Clamps to clamp the pipe into place. Works like a charm.
Here is the Summit racing clamp. I used two of them, one on each end. Check your pipe size, to make sure you get the right size clamp. They are NOT adaptable to different sizes, you have to order the correct size or it will not work.
http://store.summitracing.com/partde...5&autoview=sku
Here is what I used to cut the exhaust pipe.
http://www.mactools.com/Mac/Mac+Prod.../Exhaust/MT770
I got mine at Autozone. It is not mac brand, but it works just fine. Cost maybe $25?
https://www.rx7club.com/showpost.php...65&postcount=3
I used my exhaust cuttoff tool to make an even cut about 3" or 4" from each end of the cat. I removed the cat and measured the length of the assembly. I then cut the same length less 1/8 " out of a new blank piece of exhaust piping (bought at Pep Boys). I used the Summit Clamps to clamp the pipe into place. Works like a charm.
Here is the Summit racing clamp. I used two of them, one on each end.
Check your pipe size, to make sure you get the right size clamp. They are NOT adaptable to different sizes, you have to order the correct size or it will not work.http://store.summitracing.com/partde...5&autoview=sku
Here is what I used to cut the exhaust pipe.
http://www.mactools.com/Mac/Mac+Prod.../Exhaust/MT770
I got mine at Autozone. It is not mac brand, but it works just fine. Cost maybe $25?
I see i made a few mistake with the compression test. For one i used the top plug holes.
Another is that i only ran the compression test for 3 rotor faces then called it quits, it might have gone higher had i let it go longer (i know on my piston engines it can take quite a few to reach max pressure)
I had WAY to much oil in the rotors from using both Pre-mix and OMP.
My tester has a ather long hose (18" inches).
All combined i am pretty sure that it woud be over 100psi if i did it right. Which is really right on for an engine rebuilt about 10k ago.
Ok, about he exahust. Thanks for the links again, i had never even heard about those kind of exahust clamps. They really seal and don't leak? is so they that is what i will be doing.
08-31-08, 11:57 AM
#22
Thanks for the links!
I see i made a few mistake with the compression test. For one i used the top plug holes.
Another is that i only ran the compression test for 3 rotor faces then called it quits, it might have gone higher had i let it go longer (i know on my piston engines it can take quite a few to reach max pressure)
I had WAY to much oil in the rotors from using both Pre-mix and OMP.
My tester has a ather long hose (18" inches).
All combined i am pretty sure that it woud be over 100psi if i did it right. Which is really right on for an engine rebuilt about 10k ago.
Ok, about he exahust. Thanks for the links again, i had never even heard about those kind of exahust clamps. They really seal and don't leak? is so they that is what i will be doing.
I see i made a few mistake with the compression test. For one i used the top plug holes.
Another is that i only ran the compression test for 3 rotor faces then called it quits, it might have gone higher had i let it go longer (i know on my piston engines it can take quite a few to reach max pressure)
I had WAY to much oil in the rotors from using both Pre-mix and OMP.
My tester has a ather long hose (18" inches).
All combined i am pretty sure that it woud be over 100psi if i did it right. Which is really right on for an engine rebuilt about 10k ago.
Ok, about he exahust. Thanks for the links again, i had never even heard about those kind of exahust clamps. They really seal and don't leak? is so they that is what i will be doing.
11-09-08, 07:49 PM
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i kinda have the same thing going on right now as well.
i did some minor and major tune up stuff, replaced plugs, wires, air filter, and what not..
but i still feel like the engine is being choked out.
i was looking at the straight pipe from rx7.com
here is the link to the page.
http://www.rx7.com/store/rx7/fcexhaust.html
after that i was thinking of replaced the fuel pump.
i'm thinking that will solve my problems?
i did some minor and major tune up stuff, replaced plugs, wires, air filter, and what not..
but i still feel like the engine is being choked out.
i was looking at the straight pipe from rx7.com
here is the link to the page.
http://www.rx7.com/store/rx7/fcexhaust.html
after that i was thinking of replaced the fuel pump.
i'm thinking that will solve my problems?
11-09-08, 08:12 PM
#24
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i kinda have the same thing going on right now as well.
i did some minor and major tune up stuff, replaced plugs, wires, air filter, and what not..
but i still feel like the engine is being choked out.
i was looking at the straight pipe from rx7.com
here is the link to the page.
http://www.rx7.com/store/rx7/fcexhaust.html
after that i was thinking of replaced the fuel pump.
i'm thinking that will solve my problems?
i did some minor and major tune up stuff, replaced plugs, wires, air filter, and what not..
but i still feel like the engine is being choked out.
i was looking at the straight pipe from rx7.com
here is the link to the page.
http://www.rx7.com/store/rx7/fcexhaust.html
after that i was thinking of replaced the fuel pump.
i'm thinking that will solve my problems?
i had a some what different problem(cat turned cherry red) and just took the main cat off and gutted it and it works fine. i noticed a power increase and a completely different exhaust tone with my stock setup. Well worth gutting plus its free if you do it yourself.
11-10-08, 05:23 AM
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Tell you what. I had a neighbor take his Protoge to that shop you mentioned. They installed the two new 02 sensors in his exhaust.
Wired the 4 wire sensors wrong. Had the 02 output and gnd wires of the sensors wired *** backwards. Charged 80 bucks and didn't know he wired 'em wrong and couldn't figure out why they were getting a engine check light. Jezzus H Christ.
Wired the 4 wire sensors wrong. Had the 02 output and gnd wires of the sensors wired *** backwards. Charged 80 bucks and didn't know he wired 'em wrong and couldn't figure out why they were getting a engine check light. Jezzus H Christ.