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-   -   Trailing 2 timing way off... (https://www.rx7club.com/new-member-rx-7-technical-256/trailing-2-timing-way-off-1000733/)

RXSpeed16 06-08-12 12:04 AM

The initial set coupler just sets the BAC duty cycle so you can get the idle around 750. You didn't hurt anything. What RPM are you setting the timing at? If it's over ~1300ish, the ecu will advance the timing and you can't set the timing when it's in that mode.

It could be that the spark is arcing to the block instead of through the spark plug.

All 2nd gen coils are the same. Again, the T2 (and T1) timing is controlled by the ecu and is not adjustable. So in order for it to be off, it would have to re-program itself. Twice. Maybe your CAS is bad?

What does it sound like when you try to start it without the starter fluid? Just sad cranking or angry popping?

Wrong pulley could be an issue. You're absolutely sure you are lining up the dimple on the CAS not a hole for the split pin?

Vert88t2 06-08-12 01:11 AM

I had the idle at 750-800

It is an 88 NA harness with 87 T2 ecu and s5 block so maybe the wire that controls the trailing 2 at the ecu is in a different spot from 88na plug to 87t2 ecu?

CAS is good checked with ohm meter and check out at 158.7 ohms.

When I start it, it just cranks not even a sputter. I have to spray it with fluid AND pump the gas to get it to start.

And yes totally sure in lining up the dimple and not the pin on the CAS gear to the shaft notch. With the pulley set at the yellow mark and stabbing it in making sure it hasn't moved off my mark. I've done it like 10 times to make sure.

And when I took out the plugs the T1 plug porcilin cracked off the plug? So maybe that one was arching but would that effect T2?

37smitty 06-08-12 04:39 AM

These plugs foul at the drop of a hat. check that before you drive yourself nuts. If you have a multimeter set it to thehighest ohm scale and test between the metal twist on cap and the metal base( don't touch the leads it will read throug you). In a perfect world it will show open. Or you could go the practical route and take a plug that sparks and move it to that wire and see if it sparks on the T2 wire. If there is no spark swap a none good wire to that coil and try again. If still no spark now it's time to get serious. I would hink it would be the coil/igniter or your toggle signal. The trailing uses the same signal wire to fire T1 and T2 and there is another signal that toggles that signal to the proper coil. Start with the basics slow down and think you'll save yourself alot of time and agravation.
Dave

Vert88t2 06-08-12 12:28 PM


Originally Posted by 37smitty (Post 11117269)
These plugs foul at the drop of a hat. check that before you drive yourself nuts. If you have a multimeter set it to thehighest ohm scale and test between the metal twist on cap and the metal base( don't touch the leads it will read throug you). In a perfect world it will show open. Or you could go the practical route and take a plug that sparks and move it to that wire and see if it sparks on the T2 wire. If there is no spark swap a none good wire to that coil and try again. If still no spark now it's time to get serious. I would hink it would be the coil/igniter or your toggle signal. The trailing uses the same signal wire to fire T1 and T2 and there is another signal that toggles that signal to the proper coil. Start with the basics slow down and think you'll save yourself alot of time and agravation.
Dave

Do you know by chance which wire is the toggle wire?
Thanx Dave. I'll take all this info and sit on it for a bit. Unfortunately I can't just get new plugs so I have to order them. So it gives me some time to think about all this.

RotaryEvolution 06-08-12 02:07 PM

sorry guys but i couldn't stand to read more than 1/3 of the front page as my head was starting to hurt...


if your "T" timing is reading the same when you were using a timing light then you were checking the LEADING ignition wires, and they will read out the same.

the TRAILING wires come from the coil pack nearest the firewall and connect to the upper plugs, LEADING comes from the coil pack by the headlight and connects to the bottom plugs.

leading is wasted spark and generally you will notice with a timing light the marks on the pulley show up fine with both #1 and #2(depends if your timing light is sensitive enough to pick up the waste spark ignition cycle). switching the leading wires around won't make a difference to the engine. trailing #1 will read on the pulley, trailing #2 will not show as it is 180* off the trailing mark on the pulley.

leadings are the most important, an engine may run on trailings but i rarely even test trailings. an engine will run like ass without leadings.

i'm not sure why you are so focused on timing, it sounds like your timing was originally fine and now you have created an additional problem.

Vert88t2 06-08-12 04:32 PM


Originally Posted by Karack (Post 11117656)
sorry guys but i couldn't stand to read more than 1/3 of the front page as my head was starting to hurt...


if your "T" timing is reading the same when you were using a timing light then you were checking the LEADING ignition wires, and they will read out the same.

the TRAILING wires come from the coil pack nearest the firewall and connect to the upper plugs, LEADING comes from the coil pack by the headlight and connects to the bottom plugs.

leading is wasted spark and generally you will notice with a timing light the marks on the pulley show up fine with both #1 and #2(depends if your timing light is sensitive enough to pick up the waste spark ignition cycle). switching the leading wires around won't make a difference to the engine. trailing #1 will read on the pulley, trailing #2 will not show as it is 180* off the trailing mark on the pulley.

leadings are the most important, an engine may run on trailings but i rarely even test trailings. an engine will run like ass without leadings.

i'm not sure why you are so focused on timing, it sounds like your timing was originally fine and now you have created an additional problem.

Trailing will not show on the leading mark on the pulley that's why there is a leading AND a trailing mark on the pulley. And if trailing 1 is the only mark on the pulley and trailing 2 will be 180 deg off then why would both leading 1&2 show up on the pulley mark??? I understand that trailing is wasted spark blah blah blah I heard that 20 times already. But from factory the trailing is on time and that's the way I want it. So stop telling me to forget about it please and just focus on helpin me figure this out. Until I get the new wires and plugs in I can't check anything so once they are in I'll check to see if it's gonna start and put it in time with leading 1&2 and trailing 1. Then I'll focus on trailing 2 at a later date and focus on why it won't start on its own without starting fluid.

RXSpeed16 06-08-12 05:51 PM


Originally Posted by Vert88t2 (Post 11117781)
Trailing will not show on the leading mark on the pulley that's why there is a leading AND a trailing mark on the pulley. And if trailing 1 is the only mark on the pulley and trailing 2 will be 180 deg off then why would both leading 1&2 show up on the pulley mark??? I understand that trailing is wasted spark blah blah blah I heard that 20 times already. But from factory the trailing is on time and that's the way I want it. So stop telling me to forget about it please and just focus on helpin me figure this out. Until I get the new wires and plugs in I can't check anything so once they are in I'll check to see if it's gonna start and put it in time with leading 1&2 and trailing 1. Then I'll focus on trailing 2 at a later date and focus on why it won't start on its own without starting fluid.

We keep telling you because you aren't listening. The LEADING ignition is a wasted spark system. Meaning L1 and L2 fire simultaneously. Thus, 1 leading timing mark can be used for both events.

Trailing is NOT wasted spark. T1 and T2 should be offset 180 degrees, which you found out. You can check T1 with the trailing pulley mark. It is odd that there is a timing mark when trailing timing is not independantly adjustable from leading. But it is what it is.

Agreed, focus on the starting issue.

Vert88t2 06-08-12 06:29 PM


Originally Posted by RXSpeed16 (Post 11117829)
We keep telling you because you aren't listening. The LEADING ignition is a wasted spark system. Meaning L1 and L2 fire simultaneously. Thus, 1 leading timing mark can be used for both events.

Trailing is NOT wasted spark. T1 and T2 should be offset 180 degrees, which you found out. You can check T1 with the trailing pulley mark. It is odd that there is a timing mark when trailing timing is not independantly adjustable from leading. But it is what it is.

Agreed, focus on the starting issue.

Ok I get it now... I'm sorry if I sound like an arguemenitive person I just want to get to the bottom of this and I really didn't understand how the ignition is designed... Quick question: how can both leading fire at the same time? If the rotors are in defferant positions how could they effectively fire at the same time? I'm just tryin to wrap my head around this 😳 now I'm looking for that initial set coupler but the only thing I see that could be it has two wires at the clip one is green other is black. I don't want to jumper the wrong thing does anyone have a picture of this coupler? Or an exact wire color for the coupler?

RXSpeed16 06-08-12 06:56 PM

The initial set coupler is used to set the idle speed correctly. Correct idle speed is needed to set timing. Since your idle speed is already good, you don't need to use it. It is the only two-wire green plastic connector just behind the driver headlight. It's next to a 6-wire green plastic connector.

Karack discussed wasted spark in this thread here.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/waste-spark-direct-fire-explained-rotary-applications-984864/

Vert88t2 06-08-12 08:00 PM

Ok well I think I did a boo boo... The idle speed was at 1500 I changed it by unscrewing the screw that the throttle cable cam sits against. I don't know if it was ever tampered with before i got the car, but as I did this and set the car in time ( before I removed the CAS and can't get it to start again ) it ran great with no hesitation for the first time. And awesome that thread is a great learning thread thanx!!!

37smitty 06-08-12 09:13 PM

while your waitng for parts get to a computer and google rotary motor animation. watch a couple of those. It should answer some questions. You can see how the waste spark works. It is simply wasted it does nothing on the rotor that is not in the compression/power portion of the event.
Dave

Vert88t2 06-08-12 09:58 PM

Hmm I'll have to look at that. All the videos I've seen before never showed any spark besides when compression happens...

Vert88t2 06-08-12 10:57 PM


Originally Posted by Karack (Post 11117656)
sorry guys but i couldn't stand to read more than 1/3 of the front page as my head was starting to hurt...


if your "T" timing is reading the same when you were using a timing light then you were checking the LEADING ignition wires, and they will read out the same.

the TRAILING wires come from the coil pack nearest the firewall and connect to the upper plugs, LEADING comes from the coil pack by the headlight and connects to the bottom plugs.

leading is wasted spark and generally you will notice with a timing light the marks on the pulley show up fine with both #1 and #2(depends if your timing light is sensitive enough to pick up the waste spark ignition cycle). switching the leading wires around won't make a difference to the engine. trailing #1 will read on the pulley, trailing #2 will not show as it is 180* off the trailing mark on the pulley.

leadings are the most important, an engine may run on trailings but i rarely even test trailings. an engine will run like ass without leadings.

i'm not sure why you are so focused on timing, it sounds like your timing was originally fine and now you have created an additional problem.

Sorry Karack, I just fully read the thread you made on this subject and I get it now! It didn't logically make sense to me til I read you thread... Now that I understand the way this goes I guess I really should have left it alone when I had the timing right all along!!! Damnit! O well gotta learn somehow... New plugs and wires are on order I'll go from there. Thanx for dealing with my ignorance lol

RotaryEvolution 06-09-12 10:58 AM


Originally Posted by Vert88t2 (Post 11117858)
Ok I get it now... I'm sorry if I sound like an arguemenitive person I just want to get to the bottom of this and I really didn't understand how the ignition is designed... Quick question: how can both leading fire at the same time? If the rotors are in defferant positions how could they effectively fire at the same time? I'm just tryin to wrap my head around this �� now I'm looking for that initial set coupler but the only thing I see that could be it has two wires at the clip one is green other is black. I don't want to jumper the wrong thing does anyone have a picture of this coupler? Or an exact wire color for the coupler?

waste spark is 2 coils wired in series, so the trigger for the leading coils to spark fires both at the same time.

basically it is a cheap and effective way of firing 2 chambers with only 1 trigger circuit.


edit: don't worry too much about it, i usually get more irritated with people so willing to help that they ignore the symptoms that point to something else but help you cause further issues without steering you in the right direction.

Vert88t2 06-09-12 03:07 PM


Originally Posted by Karack (Post 11118467)
don't worry too much about it, i usually get more irritated with people so willing to help that they ignore the symptoms that point to something else but help you cause further issues without steering you in the right direction.

Yes I get that. I appreciate all the help but my car was in perfect time as I just learned and now I have gone backwards with dealing with the issue... But you live and learn... Thanks for that great knowledge your spreading to teach others like me!

Vert88t2 06-10-12 10:26 AM

Ok so I got the plugs and wires installed. Car is back to "normal" which by that I mean it's in time, and starting only with starting fluid. Now what?

satch 06-10-12 10:51 AM


Originally Posted by Vert88t2 (Post 11119245)
Ok so I got the plugs and wires installed. Car is back to "normal" which by that I mean it's in time, and starting only with starting fluid. Now what?

Are you willing to listen?

Vert88t2 06-10-12 01:05 PM


Originally Posted by satch (Post 11119275)
Are you willing to listen?

Of coarse, That's why I'm here

satch 06-10-12 01:14 PM


Originally Posted by Vert88t2 (Post 11119380)
Of coarse, That's why I'm here

Then measure the ohms of the Thermosensor as suggested. You place the part of the sensor that is in charge of reading the coolant temp in water and leaving the two terminals exposed to air and check the ohm reading from these two terminals when the water temp is at 68 degrees and also at 176 degrees and see what you get. You could also disconnect the plug at the ECU housing the G/W wire and disconnect the plug to the sensor and ohm out that wire to see if you find a fault in the wire or not. If there is no fault in the wire then the problem must arise from other source(s). And you have still yet to clarify what it means when you say the car runs fine after being started w/the assistance of starter fluid. When this fluid is used to test the engine the car usually starts up but dies out within moments. Is this what is happening to your car or does it continue to run as if there is no problem at all.

Vert88t2 06-10-12 01:21 PM


Originally Posted by satch (Post 11119388)
Then measure the ohms of the Thermosensor as suggested. You place the part of the sensor that is in charge of reading the coolant temp in water and leaving the two terminals exposed to air and check the ohm reading from these two terminals when the water temp is at 68 degrees and also at 176 degrees and see what you get. You could also disconnect the plug at the ECU housing the G/W wire and disconnect the plug to the sensor and ohm out that wire to see if you find a fault in the wire or not. If there is no fault in the wire then the problem must arise from other source(s). And you have still yet to clarify what it means when you say the car runs fine after being started w/the assistance of starter fluid. When this fluid is used to test the engine the car usually starts up but dies out within moments. Is this what is happening to your car or does it continue to run as if there is no problem at all.

I'll get on testing that thermo sensor. No when the car is started with the fluid it stays running as long as I want it too til I turn the key off. It runs great when I test drive it. It stays running/driving til I turn the key off.

satch 06-10-12 01:36 PM


Originally Posted by Vert88t2 (Post 11119394)
I'll get on testing that thermo sensor. No when the car is started with the fluid it stays running as long as I want it too til I turn the key off. It runs great when I test drive it. It stays running/driving til I turn the key off.

Then there is either too much gas in the rotor housings upon start up or too little. If its too little then a faulty Sensor signal would cause that as that sensor defaults to a warm engine setting at start up which is normally not enough fuel to start a cold engine but it should be enough to start a warm engine so when you drive the car and turn it off the engine "should" be warm and thus the engine should start w/a small amount of fuel as compared to a cold engine. You still need to fix the erroneous thermosensor signal.

If your engine actually has too much fuel then perhaps you have a flooding issue going on. This could be caused by leaky injectors. To properly deflood an engine you pull the Circuit Opening Relay, which effectively cuts power to the fuel pump. This relay is Yellow and Black and has 5 wires, Solid Black on the bottom far left position and Brown wire on the bottom far right position (and 3 wires on the top row). The relay is located under the dash just to the right of the steering column. After the relay is pulled you spray 1 to 2 seconds of starter fluid and "no more" into the intake followed by an attempt to start the car. If the car starts it will die soon after. Repeat this process one to two more times then reinstall the relay and try to start the car in a normal manner. And if you don't know this, but the gas pedal is not used on a normal start up as it could flood the engine in doing so. And there are also hot starting components to the car that could be playing a role.

Another thing is your compression might be rather low and helping to contribute to your starting problem.

RotaryEvolution 06-10-12 01:37 PM

did you try jumpering the fuel pump test connector also? could simply be a bad AFM.

Vert88t2 06-10-12 02:12 PM


Originally Posted by Karack (Post 11119402)
did you try jumpering the fuel pump test connector also? could simply be a bad AFM.

I tested the afm with the ohm meter and all checked out good. I hotwired the fuelpump to a switch thinking of this issue but it didn't change anything. But when I turn the pump on I can hear the fuel injectors spraying very loud. One seemed leaky when I tore it down. I put in new o rings but havent checked it since but it sounds like they are spraying pretty hard.

Vert88t2 06-10-12 02:15 PM


Originally Posted by Karack (Post 11119402)
did you try jumpering the fuel pump test connector also? could simply be a bad AFM.

I tested the afm with the ohm meter and all checked out good. I hotwired the fuelpump to a switch thinking of this issue but it didn't change anything. But when I turn the pump on I can hear the fuel injectors spraying very loud. One seemed leaky when I tore it down. I put in new o rings but havent checked it since but it sounds like they are spraying pretty hard. It shows at idle 36 lbs of fuel pressure

Vert88t2 06-10-12 02:25 PM


Originally Posted by Karack (Post 11119402)
did you try jumpering the fuel pump test connector also? could simply be a bad AFM.


Originally Posted by satch (Post 11119401)
Then there is either too much gas in the rotor housings upon start up or too little. If its too little then a faulty Sensor signal would cause that as that sensor defaults to a warm engine setting at start up which is normally not enough fuel to start a cold engine but it should be enough to start a warm engine so when you drive the car and turn it off the engine "should" be warm and thus the engine should start w/a small amount of fuel as compared to a cold engine. You still need to fix the erroneous thermosensor signal.

If your engine actually has too much fuel then perhaps you have a flooding issue going on. This could be caused by leaky injectors. To properly deflood an engine you pull the Circuit Opening Relay, which effectively cuts power to the fuel pump. This relay is Yellow and Black and has 5 wires, Solid Black on the bottom far left position and Brown wire on the bottom far right position (and 3 wires on the top row). The relay is located under the dash just to the right of the steering column. After the relay is pulled you spray 1 to 2 seconds of starter fluid and "no more" into the intake followed by an attempt to start the car. If the car starts it will die soon after. Repeat this process one to two more times then reinstall the relay and try to start the car in a normal manner. And if you don't know this, but the gas pedal is not used on a normal start up as it could flood the engine in doing so. And there are also hot starting components to the car that could be playing a role.

Another thing is your compression might be rather low and helping to contribute to your starting problem.

I'll check out that relay idea. It could be flooding when I turn on the fuel pump (by switch) I can hear the injectors spraying pretty hard and it shows 40lbs of fuel pressure but once the car is started it shows 36lbs.


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