AAV and Port air valve.
02-10-10, 08:40 AM
#1
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AAV and Port air valve.
90' Vert NA
I am having freaky issues with idle and it isn't vacuum leaks nor sensors. replaced all of the lines and checked all the sensors, replacing the ones that wheren't any good.
Anyway, I cannot get my car to idle at 750rpm. The problem is intermittent. I could come to a stop light and it idles fine...may hunt up and down a but around 750 but okay. Next stop light, it idles like *** at roughly a notch above 0 and the exhaust sounds strange. I "Think" I am running WAY lean at idle, somehow.
The TPS was just replaced recently.
So, would it fry my cat if I disabled the Port air valve so i can get an indication of fuel mixture at idle, and while stopped at a light at idle? For some reason, I also think something is amiss with the ACV unit in general. I just passed emissions with flying colors so I would imagine my split air function is as good as gold, but I am wavering toward one of the other functions being the culprit.
I am having freaky issues with idle and it isn't vacuum leaks nor sensors. replaced all of the lines and checked all the sensors, replacing the ones that wheren't any good.
Anyway, I cannot get my car to idle at 750rpm. The problem is intermittent. I could come to a stop light and it idles fine...may hunt up and down a but around 750 but okay. Next stop light, it idles like *** at roughly a notch above 0 and the exhaust sounds strange. I "Think" I am running WAY lean at idle, somehow.
The TPS was just replaced recently.
So, would it fry my cat if I disabled the Port air valve so i can get an indication of fuel mixture at idle, and while stopped at a light at idle? For some reason, I also think something is amiss with the ACV unit in general. I just passed emissions with flying colors so I would imagine my split air function is as good as gold, but I am wavering toward one of the other functions being the culprit.
02-10-10, 09:27 AM
#2
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Thoughts? I am getting ready for work and would like to test this out on my way there.
(eff it, I am just going to do it, I'll post results).
(eff it, I am just going to do it, I'll post results).
Last edited by jjwalker; 02-10-10 at 09:40 AM.
02-10-10, 10:04 AM
#4
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I'll do the test, see where we are A/F ratio wise, report back and we can go from there. It's freaky, sometimes it seems to run lean, and sometimes it seems to run rich.
02-10-10, 11:49 AM
#5
The port air solenoid does almost nothing. The wire broke off on my NA engine's port air solenoid, and I still passed smog. The relief valve/solenoid & switching valve/solenoid are responsible for the large check-valved path to the exhaust ports. The path behind the port air solenoid is tiny. The split air solenoid is almost as useless actually. It's only open in 5th gear, and still does 2% of the job the port air path does. Passing smog more or less says your ACV is functioning correctly. See page 4B-38 of the FSM for a diagram of the ACV paths.
Monitoring idle/low throttle AFRs with a functional emissions system on the other hand is not so easy. You'll need to force the relief valve to open at idle, so it will dump air rather than dilute your exhaust gases. Turbo relief valves use air pressure to stay closed, so pull the line off of it and it will cut off all air flow to the exhaust.
Have you considered a vacuum leak or leak at the TID? Most idle problems are due to leaks.
Monitoring idle/low throttle AFRs with a functional emissions system on the other hand is not so easy. You'll need to force the relief valve to open at idle, so it will dump air rather than dilute your exhaust gases. Turbo relief valves use air pressure to stay closed, so pull the line off of it and it will cut off all air flow to the exhaust.
Have you considered a vacuum leak or leak at the TID? Most idle problems are due to leaks.
02-10-10, 12:48 PM
#6
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Never jumper the two socket BAC valves electrical connector. I've no idea why one would do that to be truthful.
On a non turbo you just pull the BLUE connector off the Relief solenoid to make the ACV dump all the air out the silencer in the right front fender.
Split Air pipe has zippity to do with passing emissions imho.
What are you measuring the afr's with?????
The BAC maintains a idle of 750rpm IF the rpms are under that figure without the BAC connected up. There should be a change in the idle speed if your idling with a hot engine and you pull the BAC plug off and put it back on later.
Passing emissions shows the catalytic converter is good and not clogged up imho.
IF this was a turbo engine and you wanted to send all airpump air out to the silencer in the fender instead of the exhaust ports, you'd pull the vacuum line off the ACV that sticks straight up towards the hood.. But yours is NOT a turbo so you just pull the blue plug off the Relief solenoid to keep the ACV from sending air to the exhaust ports.
On a non turbo you just pull the BLUE connector off the Relief solenoid to make the ACV dump all the air out the silencer in the right front fender.
Split Air pipe has zippity to do with passing emissions imho.
What are you measuring the afr's with?????
The BAC maintains a idle of 750rpm IF the rpms are under that figure without the BAC connected up. There should be a change in the idle speed if your idling with a hot engine and you pull the BAC plug off and put it back on later.
Passing emissions shows the catalytic converter is good and not clogged up imho.
IF this was a turbo engine and you wanted to send all airpump air out to the silencer in the fender instead of the exhaust ports, you'd pull the vacuum line off the ACV that sticks straight up towards the hood.. But yours is NOT a turbo so you just pull the blue plug off the Relief solenoid to keep the ACV from sending air to the exhaust ports.
02-10-10, 01:17 PM
#7
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Strange.
AFR's are stoic with the relief being dumped out. I drove around with the switching solenoid unplugged (grey connector) and I gained a shitload of lost power. Thatis butt dyno but it is a very noticeable change in torque compared to before. That is interesting. Now I am wondering if the check valve for the split air pipe isn't leaking exhaust back into the motor. I don't have any explanation for that. Disconnecting the switching valve "SHOULD" close the split air pipe correct?
Disconnecting both made the car run badly.
I dunno, I need to fool with it and see what i find and do some more vacuum leak checks in case i missed something. This is an intermittent problem though. Sometimes the car idles high at 1200rpm and sometimes it idles at 250rpm...no ryme nor reason.
AFR's are stoic with the relief being dumped out. I drove around with the switching solenoid unplugged (grey connector) and I gained a shitload of lost power. Thatis butt dyno but it is a very noticeable change in torque compared to before. That is interesting. Now I am wondering if the check valve for the split air pipe isn't leaking exhaust back into the motor. I don't have any explanation for that. Disconnecting the switching valve "SHOULD" close the split air pipe correct?
Disconnecting both made the car run badly.
I dunno, I need to fool with it and see what i find and do some more vacuum leak checks in case i missed something. This is an intermittent problem though. Sometimes the car idles high at 1200rpm and sometimes it idles at 250rpm...no ryme nor reason.
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02-11-10, 08:28 AM
#8
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I was playing with the car last night and it seems to actually be timing related. My timing is spot on. Hell, the original blind cap from the factory is still on the CAS (factory engine).
Under 1200 rpm it idles like **** intermittently, over 1200 it smooths out and is okay. For in stance, when the car is idling poorly, I can slowly depress the accelerator and go up in rpm slightly, and it will still run poorly, but once I hit the 1200 rpm mark it all of the sudden smooths out like there is nothing wrong. At idle, the ECU had the timing so off, my car sounds lopey like a cammed out v8. My compression is fine (95ish all around).
So now I am confused. Disconnecting the split air solenoid gives more torque...noticeably, and my timing is off at idle.
What would cause the ECU to do incorrect timing corrections at idle? I know the sensors involved in that calculation, but they all tested fine so I am at an extreme loss here.
Under 1200 rpm it idles like **** intermittently, over 1200 it smooths out and is okay. For in stance, when the car is idling poorly, I can slowly depress the accelerator and go up in rpm slightly, and it will still run poorly, but once I hit the 1200 rpm mark it all of the sudden smooths out like there is nothing wrong. At idle, the ECU had the timing so off, my car sounds lopey like a cammed out v8. My compression is fine (95ish all around).
So now I am confused. Disconnecting the split air solenoid gives more torque...noticeably, and my timing is off at idle.
What would cause the ECU to do incorrect timing corrections at idle? I know the sensors involved in that calculation, but they all tested fine so I am at an extreme loss here.
02-11-10, 09:33 AM
#9
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Air pump air should not be going into the intake manifold except when the car is being driven and you let off the pedal all the way. That creates a vacuum at the anti afterburn valve (internal to the ACV) and the anti afterburn valve lets a small amount of air into a intake runner to prevent ..backfire. That small amount of air goes thru a hole about 1/32" in diameter (ain't much air).
Other than that the airpump air does not go into the intake manifold. Normally it goes either into the path from the ACV to the exhaust ports.....or other times the air gets dumped into the silencer in the right front fender........and some at times goes into the split air pipe.
The grey switching solenoid at idle is not energized. The switching solenoid is energized at given times when the car is actually being driven. Those times vary.
You know the TPS check connector and how you can use two LED's to set the TPS????? The lighting up of those two LEDS indicates whether the Relief or Switchig solenoids are being energized. Norally with a fully hot engine and at idle, only one of those lights is lit up. That light would be indication the Relief solenoid is energized. The other LED that is not lit up indicates the Switching solenoid is not energized.
The two solenoids act mirror opposite of each other because of the way the vacuum lines are connected to the two solenoids and where the small air filter is located on the solenoid. Take a look at 'em and you'll see what I mean.
When energized the relief solenoid passes vacuum from one of it's nipples to the other. The opposite is true of the switching solenoid. When IT is De-energized it passes vaccuum from one nippele to the other.
De=energize the relief solenoid and it does not pass vacuum from one nipple to the other therefore removing vacuum from it's feed to the ACV and causes the ACV to dump the airpum air into the silencer in the right front fender. IF you energize the relief solenoid, then vacuum is now sent to the ACV's relief diaphram and the airpump air is now sent to the exhaust ports.
The switching solenoid when de energized sends vacuum to the switching diaphram inside the ACV which causes airpump air to go to the split air pipe, BUT if the relief solenoid is de energized at that same time, little to no air will actually go to the split air pipe (remember if the relief diaphram inside the ACV does not see vacuum, then the air gets dumped into the right front fender). The reason for little or no air going to the split air pipe even with the switching soleniod de energized is because most air is being dumped in the silencer so there isn't much if any airpump pressure to send air to the split air pipe.
Most of this coming and going of power to the relief and switching solenoids can result ........in driving you crazy trying to figure where the airpump air is going at a given time.
All you have to do is rig up two LEDs inside the car where you can observe them when your driving. The LEDs would have to be tied to the relief and switching solenoids gnd wire and powered by some source of batt power. You could run three wires from the TPS check connector into the cabin to do this. The black/white wire in that TPS check connector would be the power for the LED and the two other wires coming from the connector would be the gnd signal from the switching and relief solenoids.
So you'd be at idle and see one LED lit up, indicating the Relief solenod energized and sending vacuum to the relief diaphram inside the ACV. And the other light not lit being the switching solenoid indicating vacuum going to the switching diaphram inside the ACV therefore closing off the path of air to the split air pipe.
Now with a fully hot engine you go driving. At sometimes only one light will be lit and at other times both lights lit up. You gotta think about what happens when either light is lit or unlit or both lit up.
IF the relief solenoid LED is unlit and the switching is lit, that indicates the airpump air is being dumped into the silencer and at the same time the switching diaphram is not getting vacuum and opening a path to the split air pipe. What good this does is a bit beyond me. But if both LEDS are lit then air will be sent to the split air pipe because the relief diaphram is not getting vacuum and there for the airpump air is NOT being dumped overboard.
Another scenario is when you've been driving over 120 second steadily. If memeory serves the relief solenoid shuts off vacuum to the relief diaphram which results in air pum air going to the silencer (being dumped so to speak) and the switching solenoid will be lit but no air can go to the split air pipe 'cause there ain't no pressure from the airpump to send it there. Anemic amount at best to the split air pipe.
That's what I know about non turbo ACV and the switching and relief solenoids and how air is sent to the exhaust ports and the split air pipe at given times.
A cold engine will send no air to the exhaust ports til the engine temp gets up to a given temp, then the relief solenoid will get energized and send air to the exhaust ports on the enigne.
The jpg attached if read, MIGHT explain how airpump air sent to the EXHAUST PORTS might effect idle speed/sound/quality. I used to be convinced no airpump air gets into the intake system except when the anti afterburn valve in the ACV operates, but reading the attached jpg indiactes to me that airpump air mixed AT the exhaust ports can find its way into the intake on the intake stroke as explained in the attached jpg.
Other than that the airpump air does not go into the intake manifold. Normally it goes either into the path from the ACV to the exhaust ports.....or other times the air gets dumped into the silencer in the right front fender........and some at times goes into the split air pipe.
The grey switching solenoid at idle is not energized. The switching solenoid is energized at given times when the car is actually being driven. Those times vary.
You know the TPS check connector and how you can use two LED's to set the TPS????? The lighting up of those two LEDS indicates whether the Relief or Switchig solenoids are being energized. Norally with a fully hot engine and at idle, only one of those lights is lit up. That light would be indication the Relief solenoid is energized. The other LED that is not lit up indicates the Switching solenoid is not energized.
The two solenoids act mirror opposite of each other because of the way the vacuum lines are connected to the two solenoids and where the small air filter is located on the solenoid. Take a look at 'em and you'll see what I mean.
When energized the relief solenoid passes vacuum from one of it's nipples to the other. The opposite is true of the switching solenoid. When IT is De-energized it passes vaccuum from one nippele to the other.
De=energize the relief solenoid and it does not pass vacuum from one nipple to the other therefore removing vacuum from it's feed to the ACV and causes the ACV to dump the airpum air into the silencer in the right front fender. IF you energize the relief solenoid, then vacuum is now sent to the ACV's relief diaphram and the airpump air is now sent to the exhaust ports.
The switching solenoid when de energized sends vacuum to the switching diaphram inside the ACV which causes airpump air to go to the split air pipe, BUT if the relief solenoid is de energized at that same time, little to no air will actually go to the split air pipe (remember if the relief diaphram inside the ACV does not see vacuum, then the air gets dumped into the right front fender). The reason for little or no air going to the split air pipe even with the switching soleniod de energized is because most air is being dumped in the silencer so there isn't much if any airpump pressure to send air to the split air pipe.
Most of this coming and going of power to the relief and switching solenoids can result ........in driving you crazy trying to figure where the airpump air is going at a given time.
All you have to do is rig up two LEDs inside the car where you can observe them when your driving. The LEDs would have to be tied to the relief and switching solenoids gnd wire and powered by some source of batt power. You could run three wires from the TPS check connector into the cabin to do this. The black/white wire in that TPS check connector would be the power for the LED and the two other wires coming from the connector would be the gnd signal from the switching and relief solenoids.
So you'd be at idle and see one LED lit up, indicating the Relief solenod energized and sending vacuum to the relief diaphram inside the ACV. And the other light not lit being the switching solenoid indicating vacuum going to the switching diaphram inside the ACV therefore closing off the path of air to the split air pipe.
Now with a fully hot engine you go driving. At sometimes only one light will be lit and at other times both lights lit up. You gotta think about what happens when either light is lit or unlit or both lit up.
IF the relief solenoid LED is unlit and the switching is lit, that indicates the airpump air is being dumped into the silencer and at the same time the switching diaphram is not getting vacuum and opening a path to the split air pipe. What good this does is a bit beyond me. But if both LEDS are lit then air will be sent to the split air pipe because the relief diaphram is not getting vacuum and there for the airpump air is NOT being dumped overboard.
Another scenario is when you've been driving over 120 second steadily. If memeory serves the relief solenoid shuts off vacuum to the relief diaphram which results in air pum air going to the silencer (being dumped so to speak) and the switching solenoid will be lit but no air can go to the split air pipe 'cause there ain't no pressure from the airpump to send it there. Anemic amount at best to the split air pipe.
That's what I know about non turbo ACV and the switching and relief solenoids and how air is sent to the exhaust ports and the split air pipe at given times.
A cold engine will send no air to the exhaust ports til the engine temp gets up to a given temp, then the relief solenoid will get energized and send air to the exhaust ports on the enigne.
The jpg attached if read, MIGHT explain how airpump air sent to the EXHAUST PORTS might effect idle speed/sound/quality. I used to be convinced no airpump air gets into the intake system except when the anti afterburn valve in the ACV operates, but reading the attached jpg indiactes to me that airpump air mixed AT the exhaust ports can find its way into the intake on the intake stroke as explained in the attached jpg.
02-11-10, 09:54 AM
#10
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Anyway, I forgot to tell you the following...............anytime the car is sitting in the driveway and you slowly rev the engine to over 1200 rpm (close to being the exact right figure), the ECU advances the timing and you'll notice a slight jump upwards in the rpms. The 1200 rpm is the trigger point for that to happen. That explains what you wrote in a post or two above this one.
02-11-10, 10:08 AM
#11
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Yeah, I tested with the LED method you described above HAILERS, and the valves are operating properly. The attached JPG could explain my power increase with port air on at all times, somewhat. Strange still.
Now the timing thing boggles me. I just noticed that yesterday, the timing correctiosn the ECU does below 1200rpm. It is intermittent. Sometiems my engine idles as 1100-1200rpm and sometimes it idles at 250rpm. It almost seems as if the ECU is either running extremely retarded causing the high idle speed or extremely advanced causing the lopey low idle at 250rpm. My sensors checked fine, the ones involved with engine timing.
I am going to pull the car in the garage and mess with it and run some tests before work. I am beyond confused as to what would cause the timing issue. I'll post back with my findings.
EDIT: you replied while I was replying.
So based on what you are saying, the ECU is rather "retarding" the timing and causing the shitty idle?
EDIT2: Woah, just thought of something. My CPU is all kinds of messed up. High beams dont work, alarm doesn't work, so on....
Now, I know the CPU has a hand in sending the load condition signals to the ECU. I am curious as to maybe my borked CPU is to blame.
Now the timing thing boggles me. I just noticed that yesterday, the timing correctiosn the ECU does below 1200rpm. It is intermittent. Sometiems my engine idles as 1100-1200rpm and sometimes it idles at 250rpm. It almost seems as if the ECU is either running extremely retarded causing the high idle speed or extremely advanced causing the lopey low idle at 250rpm. My sensors checked fine, the ones involved with engine timing.
I am going to pull the car in the garage and mess with it and run some tests before work. I am beyond confused as to what would cause the timing issue. I'll post back with my findings.
EDIT: you replied while I was replying.
So based on what you are saying, the ECU is rather "retarding" the timing and causing the shitty idle?
EDIT2: Woah, just thought of something. My CPU is all kinds of messed up. High beams dont work, alarm doesn't work, so on....
Now, I know the CPU has a hand in sending the load condition signals to the ECU. I am curious as to maybe my borked CPU is to blame.
Last edited by jjwalker; 02-11-10 at 10:17 AM.
02-11-10, 10:43 AM
#12
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******Sometiems my engine idles as 1100-1200rpm and sometimes it idles at 250rpm. It almost seems************
Almost sounds like a BAC valve sticking open a touch more than it should and keeping the rpms at just above 1200 rpm.
It should never idle at 250rpm if the BAC is working.
The BAC should bring the speed up close to 750 rpm if working right. The BAC occilates at approx 120hz and its duty cycle should vary with loads on the engine (like headligts on at idle).
No. NOt saying the ECU is retarding the timing. Saying the engine when over approx 1200rpm the timing will advance. There is something called FIXED TIMING and that happens below 1200 rpm. It should read the same anytime under 1200 rpm, or be FIXED TIMING under 1200rpm.
Might remove the BAC and flush it with carb cleaner several times and reinstall it. Never pry on it's valve with anything or you'll damage it. Only two nuts hold it on and a water hose.
Almost sounds like a BAC valve sticking open a touch more than it should and keeping the rpms at just above 1200 rpm.
It should never idle at 250rpm if the BAC is working.
The BAC should bring the speed up close to 750 rpm if working right. The BAC occilates at approx 120hz and its duty cycle should vary with loads on the engine (like headligts on at idle).
No. NOt saying the ECU is retarding the timing. Saying the engine when over approx 1200rpm the timing will advance. There is something called FIXED TIMING and that happens below 1200 rpm. It should read the same anytime under 1200 rpm, or be FIXED TIMING under 1200rpm.
Might remove the BAC and flush it with carb cleaner several times and reinstall it. Never pry on it's valve with anything or you'll damage it. Only two nuts hold it on and a water hose.
02-11-10, 11:46 AM
#13
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******Sometiems my engine idles as 1100-1200rpm and sometimes it idles at 250rpm. It almost seems************
Almost sounds like a BAC valve sticking open a touch more than it should and keeping the rpms at just above 1200 rpm.
It should never idle at 250rpm if the BAC is working.
The BAC should bring the speed up close to 750 rpm if working right. The BAC occilates at approx 120hz and its duty cycle should vary with loads on the engine (like headligts on at idle).
No. NOt saying the ECU is retarding the timing. Saying the engine when over approx 1200rpm the timing will advance. There is something called FIXED TIMING and that happens below 1200 rpm. It should read the same anytime under 1200 rpm, or be FIXED TIMING under 1200rpm.
Might remove the BAC and flush it with carb cleaner several times and reinstall it. Never pry on it's valve with anything or you'll damage it. Only two nuts hold it on and a water hose.
Almost sounds like a BAC valve sticking open a touch more than it should and keeping the rpms at just above 1200 rpm.
It should never idle at 250rpm if the BAC is working.
The BAC should bring the speed up close to 750 rpm if working right. The BAC occilates at approx 120hz and its duty cycle should vary with loads on the engine (like headligts on at idle).
No. NOt saying the ECU is retarding the timing. Saying the engine when over approx 1200rpm the timing will advance. There is something called FIXED TIMING and that happens below 1200 rpm. It should read the same anytime under 1200 rpm, or be FIXED TIMING under 1200rpm.
Might remove the BAC and flush it with carb cleaner several times and reinstall it. Never pry on it's valve with anything or you'll damage it. Only two nuts hold it on and a water hose.
Here is something interesting, I unplugged my Horn/airbag CPU and the problem went away, for now. I'll have to test drive it on the way to work and see what happens. I have some very serious Horn/Airbag CPU electrical gremlins, so I am thinking MAYBE the electrical load connections between the CPU and the ECU are screwing up, but like I said, I'll need to test drive. I'll report back when I get to work.
It may seem as if I am bypassing everyones advice to look directly at the BAC and I am not. I am merely exploring other ideas. Once I get a goodf stretch of time (like a day off) I'll yank it and inspect the BAC and see.
02-11-10, 11:59 AM
#14
I'll take a stab at the BAC when I get chance. Can't hurt to clean it out.
Here is something interesting, I unplugged my Horn/airbag CPU and the problem went away, for now. I'll have to test drive it on the way to work and see what happens. I have some very serious Horn/Airbag CPU electrical gremlins, so I am thinking MAYBE the electrical load connections between the CPU and the ECU are screwing up, but like I said, I'll need to test drive. I'll report back when I get to work.
It may seem as if I am bypassing everyones advice to look directly at the BAC and I am not. I am merely exploring other ideas. Once I get a goodf stretch of time (like a day off) I'll yank it and inspect the BAC and see.
Here is something interesting, I unplugged my Horn/airbag CPU and the problem went away, for now. I'll have to test drive it on the way to work and see what happens. I have some very serious Horn/Airbag CPU electrical gremlins, so I am thinking MAYBE the electrical load connections between the CPU and the ECU are screwing up, but like I said, I'll need to test drive. I'll report back when I get to work.
It may seem as if I am bypassing everyones advice to look directly at the BAC and I am not. I am merely exploring other ideas. Once I get a goodf stretch of time (like a day off) I'll yank it and inspect the BAC and see.
02-11-10, 12:05 PM
#15
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I live in DFW because it DOESN'T snow. Bullocks I say! We have about 8 inches accumulation which believe it or not is alot for here.
EDIT: NEW UPDATE! Disconnected battery because I had a bunch of trouble codes stored from plugging and unplugging stuff. Cleared the codes, started car, shut it off, then jumpered the test connector.
Code 11 = Intake air thermo sensor (engine)
Code 17 = Feedback system
Now I am really confused. The intake air thermo sensor checked out fine. I guess I'll have to test it at the ecu and see if the ECU can see the sensor.
Last edited by jjwalker; 02-11-10 at 12:13 PM.
02-11-10, 07:09 PM
#16
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Feedback shouldn't effect idle since the 02 is used only used in closed loop driving. As in actual driving the car at a steady speed over approx 15-1700 rpm. Your ECU most likely isn't seeing the signal from the 02 sensor for some reason or other. Feedback shouldn't effect idle at all. 02 not a player.
Backprobe pin 2L on the ECU with the plugs connected up and the engine idling fully warm and the meter should read b/t 1-2vdc. IF it reads close to 5vdc, then there is a wire broken/disconnected b/t the sensor and the ECU pin 2L. Series five car.
Backprobe pin 2L on the ECU with the plugs connected up and the engine idling fully warm and the meter should read b/t 1-2vdc. IF it reads close to 5vdc, then there is a wire broken/disconnected b/t the sensor and the ECU pin 2L. Series five car.
02-11-10, 10:28 PM
#17
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Well, the wiring up to the ECU is good, I know that because my A/F meter is connected about 3 inches up from the harness on the ECU. Maybe my ECU is roasty toasty or bad solder, who knows.
I started getting a check engine light on my way home from work, so it must be a new code. The light would shut off when I accelerated. We'll check in the morning and see what this new code is.
I started getting a check engine light on my way home from work, so it must be a new code. The light would shut off when I accelerated. We'll check in the morning and see what this new code is.
02-12-10, 12:17 PM
#18
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I think the ground on my trailing coil was poor.
I drove around and it seems to idle fine now. I'll have to test it on my way to work and keep my fingers crossed. That would also explain why my exhaust sounded funny.
I drove around and it seems to idle fine now. I'll have to test it on my way to work and keep my fingers crossed. That would also explain why my exhaust sounded funny.
02-12-10, 11:09 PM
#19
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*BANGS HEAD*
DAMN IT.
That wasn't it apparently. It is intemrittent. It worked on the way to work without a hitch, worked during lunch when i went to eat....on the home from work it ran like **** at idle. I am going to drown my BAC valve in carb cleaner in the morning. If that doesn't do it, I am going to drown the car in carb cleaner and set it a flame.
DAMN IT.
That wasn't it apparently. It is intemrittent. It worked on the way to work without a hitch, worked during lunch when i went to eat....on the home from work it ran like **** at idle. I am going to drown my BAC valve in carb cleaner in the morning. If that doesn't do it, I am going to drown the car in carb cleaner and set it a flame.
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Jeff20B
1st Generation Specific (1979-1985)
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09-16-18 07:16 PM
mulcryant
2nd Generation Specific (1986-1992)
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09-09-15 05:24 PM
