fixed my idle problems, backfiring, bucking and more...
01-26-07, 09:55 PM
#151
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Originally Posted by kashent
Yes.
01-26-07, 10:27 PM
#152
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Well, it's possible that your maps are so far out of whack that the PFC can't find the proper setting for your car. I'll share what knowledge I can to help you, but you'll need either a datalogic or a commander.
01-28-07, 05:09 PM
#153
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im using the base map right now that comes with the PFC. i have a commander, but not really sure what setting would really help the surging. i can fuel tune, but i am not experienced tuner like that by all means
02-12-08, 08:02 PM
#156
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just wanted to bump a good thread.
i have a 92' efini fd and the car had problems idling steadily, and was a real bitch to drive at slow speeds in 1st gear. it would also pop like crazy on deceleration coming off of boost.
getting the screws out was a pain, the bottom one you have to be careful with as it's easy to strip it. the top one i began to strip and then just decided to use pliers to undo it, i got it loose enough to finish with a screwdriver.
adjusted the voltage to the correct readings and then tightened the screws up again.
fired up the car and instantly it idled smoothly at 750rpm and stayed there. took it for a couple spins around the block in 1st and 2nd gear and it's now silky smooth, no bucking at slow speeds.
a must-do maintenance item for every fd owner with idle surging and bucking problems.
while you are adjusting the TPS, you should take a look at the MAP sensor hose going into the back of the engine. Mine was in pretty crappy shape so I just cut a new piece of 4mm ID rubber hose and slapped it on. That solved some of my unstable idle problems as well, and also reduced backfiring slightly.
i have a 92' efini fd and the car had problems idling steadily, and was a real bitch to drive at slow speeds in 1st gear. it would also pop like crazy on deceleration coming off of boost.
getting the screws out was a pain, the bottom one you have to be careful with as it's easy to strip it. the top one i began to strip and then just decided to use pliers to undo it, i got it loose enough to finish with a screwdriver.
adjusted the voltage to the correct readings and then tightened the screws up again.
fired up the car and instantly it idled smoothly at 750rpm and stayed there. took it for a couple spins around the block in 1st and 2nd gear and it's now silky smooth, no bucking at slow speeds.
a must-do maintenance item for every fd owner with idle surging and bucking problems.
while you are adjusting the TPS, you should take a look at the MAP sensor hose going into the back of the engine. Mine was in pretty crappy shape so I just cut a new piece of 4mm ID rubber hose and slapped it on. That solved some of my unstable idle problems as well, and also reduced backfiring slightly.
03-26-08, 09:26 AM
#157
bump an excellent informative thread for quick question.
brief history. i just started another thread so ill give the very basics real quick.
idles at 1100 rpm usually. occasionally will go down under a 1000 but not often. i dont really care about that part.....
VIOLENT bucking at WOT in 1st, and sometimes second gear. should not be fuel cut as im not making 10psi.
i have a similiar scenario as many in this thread. my UIM was off, and ive removed double throttle completly, and disconnected the AWS hose to install greddy elbow, left other end open(bad idea?) and that seems to be when all this started!
so what i wanted to ask. i have a PFC ready to install. however i dont have access to a commander right now. BUT i do have datalogit. ive never used any of this. can i see VAT1 and VAT2 reading from datalogit, like i could from the commander?
p.s. if anyone thinks they know what my problem is(not TPS) please chime in.
brief history. i just started another thread so ill give the very basics real quick.
idles at 1100 rpm usually. occasionally will go down under a 1000 but not often. i dont really care about that part.....
VIOLENT bucking at WOT in 1st, and sometimes second gear. should not be fuel cut as im not making 10psi.
i have a similiar scenario as many in this thread. my UIM was off, and ive removed double throttle completly, and disconnected the AWS hose to install greddy elbow, left other end open(bad idea?) and that seems to be when all this started!
so what i wanted to ask. i have a PFC ready to install. however i dont have access to a commander right now. BUT i do have datalogit. ive never used any of this. can i see VAT1 and VAT2 reading from datalogit, like i could from the commander?
p.s. if anyone thinks they know what my problem is(not TPS) please chime in.
09-22-08, 02:17 PM
#158
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I know this is an old thread but I have found it very helpful. Here is my question: In the first post to this thread, Damian listed the following symptoms of his out of whack TPS sensor:
- Idle
idle was really bad, hunted, minibackfires, airpump was coming on at funny times, it stalled a few times, sometimes it would idle high
- Rev sticking
It would stick around 3500-4000 when downrevving, it made it really weird to drive because it would not decelerate right away when you let off the gas, after a few seconds it would eventually go down
- Deceleration backfires
I would get all kinds of backfiring upon deceleration or gear shifting
- Bucking
It would buck when trying to keep a constant speed and buck very bad deceleration.
My question is, I am having EXACTLY the same issues with my FD. Unfortunately, my readings on my TPS are all within range. Is there any chance that my TPS sensor is still bad even having gotten good readings?
- Idle
idle was really bad, hunted, minibackfires, airpump was coming on at funny times, it stalled a few times, sometimes it would idle high
- Rev sticking
It would stick around 3500-4000 when downrevving, it made it really weird to drive because it would not decelerate right away when you let off the gas, after a few seconds it would eventually go down
- Deceleration backfires
I would get all kinds of backfiring upon deceleration or gear shifting
- Bucking
It would buck when trying to keep a constant speed and buck very bad deceleration.
03-23-09, 11:15 PM
#159
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im having idle issues also. my car fully warm idles at 1100 and when i drive and hit a light and stop its idling around 1300-1400 then i depress the clutch throw it into first then it drops down fast to 1000-1100 then put it into neutral and it stays. also while driving at about 30mph and i approach a stop light and while the car is moving in neutral the rpms go up and down from 1100 to 1400 until i stop. would this be the tps? i also will need pictures =( it looks so complicated and i dont know which is what yet. thanks.
09-15-09, 08:35 AM
#161
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Hi all
I also read this thread because i guess i have also a bad TPS.
I got all the tool from robrobinettes site.
Then i put a needle into the connector to read voltage, but i only get about 0,200 - 0,300 volt, also when i move the TPS up and down ( i pulled the screws out a little bit so i could move it ). Do i have a bad TPS?
To work easier with the screwdriver, i put off the throttlebody. After the reinstall, my rpms are higher then before, like 3000 - 2000 rpm. The fan-relay has been pulled to get good voltage readings.
Problems yesterday and today:
I let the car warm up, suddenly a lot of steam came out of the cabin --> the heater core blew and a lot of coolant was on the passengers side.
Today, i pulled of the hoses for the heater core and put them together. The heater core has to wait for now, i want to fix these other problems.
Then today, i let the engine warm up again, suddenly the small hose from the AST went off and hot coolant came out.
So i guess i did three mistakes:
1st: the fan relay wasnt in for warmup
2nd: the small hose on the AST wasnt secured with a hoseclamp
3rd: i have one 0,9 bar ( 13psi ) radiator cap and one 1,3 bar ( 19psi ) radiator cap.
Ok but i guess the major problem is the TPS. But how can i be sure its the TPS and not the signal to the TPS ( because i dont want to buy a expensive TPS and then i will find out, it wasnt the TPS... ).
Thx a lot for your help!!
I also read this thread because i guess i have also a bad TPS.
I got all the tool from robrobinettes site.
Then i put a needle into the connector to read voltage, but i only get about 0,200 - 0,300 volt, also when i move the TPS up and down ( i pulled the screws out a little bit so i could move it ). Do i have a bad TPS?
To work easier with the screwdriver, i put off the throttlebody. After the reinstall, my rpms are higher then before, like 3000 - 2000 rpm. The fan-relay has been pulled to get good voltage readings.
Problems yesterday and today:
I let the car warm up, suddenly a lot of steam came out of the cabin --> the heater core blew and a lot of coolant was on the passengers side.
Today, i pulled of the hoses for the heater core and put them together. The heater core has to wait for now, i want to fix these other problems.
Then today, i let the engine warm up again, suddenly the small hose from the AST went off and hot coolant came out.
So i guess i did three mistakes:
1st: the fan relay wasnt in for warmup
2nd: the small hose on the AST wasnt secured with a hoseclamp
3rd: i have one 0,9 bar ( 13psi ) radiator cap and one 1,3 bar ( 19psi ) radiator cap.
Ok but i guess the major problem is the TPS. But how can i be sure its the TPS and not the signal to the TPS ( because i dont want to buy a expensive TPS and then i will find out, it wasnt the TPS... ).
Thx a lot for your help!!
09-29-09, 07:42 AM
#163
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if you have a pfc you can check the tps voltages from there. if not , i think the only way is to use needle on the wire behind the connector terminal. the 3000 rps i think is too much to be caused by a tps. did you checked for air leaks? all the air hoses are ok?gaskets?
10-10-09, 05:35 AM
#164
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Thx for your answer, Achilles.
Suddenly i dont have a PFC but good to know that you can read it with the pfc.
Hoses are new and double checked, no air leaks - i built that pressure adapter for the air intake hose. Gaskets are new.
The 3000 are only there when you move the TPS up and down.
My car electrician will check out if he can read that TPS out, i will inform you what he says.
Suddenly i dont have a PFC but good to know that you can read it with the pfc.
Hoses are new and double checked, no air leaks - i built that pressure adapter for the air intake hose. Gaskets are new.
The 3000 are only there when you move the TPS up and down.
My car electrician will check out if he can read that TPS out, i will inform you what he says.
10-10-09, 08:06 AM
#165
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Ok, i have a bad TPS, i got following trouble codes: 11, 12, 18.
My car electrician thinks, that my grounding problem in the past could be the reason for the damaged parts, because the engine took grounding from every part with a grounding cable. That may be the reason for the damaged parts.
I guess i have to order again...
My car electrician thinks, that my grounding problem in the past could be the reason for the damaged parts, because the engine took grounding from every part with a grounding cable. That may be the reason for the damaged parts.
I guess i have to order again...
10-11-09, 03:29 AM
#166
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My problem is the TPS too. The car electrician thinks that it has been damaged with my grounding problem in the past. This means the engine took grounding from everywhere else, because there wasnt a good grounding connection to the engine.
So this could be a reason for the damaged TPS. I also got an error code for the air intake sensor...
So this could be a reason for the damaged TPS. I also got an error code for the air intake sensor...
04-24-10, 10:33 AM
#170
Really old thread. . .still really good and current advise. Adjusted my TPS (I was within spec but at the very high end of the low end settings). After adjusting, 90% of popping on decel is gone, all popping between gears on upshift is gone, and slight "bucking" while maintaining constant speed on "nuetral" throttle is gone. This is such a simple thing to do, and yet i hadn't thought to check it in years!
PS. Replace the original screws with socket head screws -- the next person to work on the TPS will thank you:-)
PS. Replace the original screws with socket head screws -- the next person to work on the TPS will thank you:-)
07-21-10, 03:18 PM
#171
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Sorry for yet ANOTHER resurrection of a zombie thread - It's a great one and shouldn't be dumped out to the thread graveyard.
I just looked at mine, and given the skew inside and outside of the whole shibang, here're my numbers:
O>1.35v C>4.99v
O>.6v C>4.46v
Now.... These numbers represent the numbers of a known working TPS (I'd gone through all of this crap before and verified that it's working) and so I came up with a solution for short-cutting the whole test, in it's entirety:
Back out the idle adjustment screw, all the way, so that it isn't touching the throttle-stop (it's the adjustment screw on the fronside of the TB), so that the TB is sitting at a non-altered position.
Do the same voltage checks that you'd normally do when checking the TPS (green+red and then Black).
If your numbers are what mine are, then your TPS should be fine, though I'm certain that someone's going to give X, Y, or Z reasons as to why this won't work as a good base-logic but doing it this way is a really quick identifier to see if you need to take on the PITA task of the entire endeavor.
Someone who's gone through the entire TPS adjustment process (therefore KNOWING their TPS is in good adjustment) should try this and post their numbers, just as a fail-safe/ redundant test.
Like I said, this IS NOT a shortcut to doing it right, just a quickie test for baseline numbers.
If these numbers are off by a bad margin, then there's probably something amiss and you should go through the entire ordeal.
I just looked at mine, and given the skew inside and outside of the whole shibang, here're my numbers:
O>1.35v C>4.99v
O>.6v C>4.46v
Now.... These numbers represent the numbers of a known working TPS (I'd gone through all of this crap before and verified that it's working) and so I came up with a solution for short-cutting the whole test, in it's entirety:
Back out the idle adjustment screw, all the way, so that it isn't touching the throttle-stop (it's the adjustment screw on the fronside of the TB), so that the TB is sitting at a non-altered position.
Do the same voltage checks that you'd normally do when checking the TPS (green+red and then Black).
If your numbers are what mine are, then your TPS should be fine, though I'm certain that someone's going to give X, Y, or Z reasons as to why this won't work as a good base-logic but doing it this way is a really quick identifier to see if you need to take on the PITA task of the entire endeavor.
Someone who's gone through the entire TPS adjustment process (therefore KNOWING their TPS is in good adjustment) should try this and post their numbers, just as a fail-safe/ redundant test.
Like I said, this IS NOT a shortcut to doing it right, just a quickie test for baseline numbers.
If these numbers are off by a bad margin, then there's probably something amiss and you should go through the entire ordeal.
01-17-11, 07:11 AM
#172
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Hope you dont mind me resurrecting this thread again. A lot of good info in it.
Im having a couple problems setting my TPS
I had a lumpy idle, with TPS values outside of spec. Measurement taken last Novemeber. I stored away my FD for the winter months and went working on it last weekend to get it ready for spring. I took off the tps and replaced the bolds with cap head bolts to allow for easier adjustment.
I warmed up the car, then shut it down. Turned on the ignition to check the values on the PFC - values are something like 0.1V and not changing when I rotate the sensor. If I rotate the sensor when the engine is running The idle changes - bounces higher, closer to stalling etc.
The fact the PFC is not picking up any values does this mean Ive a dead TPS sensor? Any help is much appreciated
Thanks
John
Im having a couple problems setting my TPS
I had a lumpy idle, with TPS values outside of spec. Measurement taken last Novemeber. I stored away my FD for the winter months and went working on it last weekend to get it ready for spring. I took off the tps and replaced the bolds with cap head bolts to allow for easier adjustment.
I warmed up the car, then shut it down. Turned on the ignition to check the values on the PFC - values are something like 0.1V and not changing when I rotate the sensor. If I rotate the sensor when the engine is running The idle changes - bounces higher, closer to stalling etc.
The fact the PFC is not picking up any values does this mean Ive a dead TPS sensor? Any help is much appreciated
Thanks
John
01-29-11, 04:06 PM
#173
So I checked my TPS voltages and the bottom wire is about 1 volt low at the upper range and a smidge low at the bottom of the range. So now to get the friggin bottom screw loose so I can adjust it. I have the phillips head screws and the bottom screw is nearly stripped from me trying to get the thing out. I disconnected the hoses as suggested as well as unscrewed and removed the oil filter to try and come from underneath with an elbow phillips. No luck.. the thing just won't budge. I even got some needle nose pliers wrapped around and it still can't get it.
Any suggestions?
Pb blast? Seems like overkill for such a small screw, but I just can't get leverage. I know one thing. If that screw comes out it will not be going back in. I picked up some hex bolts that fix perfect. Top one is good to go.
Any suggestions?
Pb blast? Seems like overkill for such a small screw, but I just can't get leverage. I know one thing. If that screw comes out it will not be going back in. I picked up some hex bolts that fix perfect. Top one is good to go.
01-31-11, 12:42 PM
#174
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Ok,
After reading through this entire thread and the links posted, it seems that I'm having some of the same problems with mine as well.
Whenever I'm in low speeds, (parking lots mostly), it's bucks pretty wild if I'm trying to hold a low speed. It requires me using my clutch to keep it from bucking back and forth. Also my idle is around 500 when fully warm.
I'm not familiar with the TPS or adjusting anything that has been mentioned, but I'm needing to fix this. I'm glad I'm not the only one with this problem.
If anyone can dumb this down a little for me, I got tools on hand, no voltmeter but I can pick one up. I'm wanting to fix this asap.
Thanks in advance.
Also I'm stock other than Intake and exhaust.
After reading through this entire thread and the links posted, it seems that I'm having some of the same problems with mine as well.
Whenever I'm in low speeds, (parking lots mostly), it's bucks pretty wild if I'm trying to hold a low speed. It requires me using my clutch to keep it from bucking back and forth. Also my idle is around 500 when fully warm.
I'm not familiar with the TPS or adjusting anything that has been mentioned, but I'm needing to fix this. I'm glad I'm not the only one with this problem.
If anyone can dumb this down a little for me, I got tools on hand, no voltmeter but I can pick one up. I'm wanting to fix this asap.
Thanks in advance.
Also I'm stock other than Intake and exhaust.