Car is running very rich. put new plugs and coil pack, car seems to run fine. When I put the car under boost it bucks and the AF meter shows rich. All sensor values are good. TPS 44-46, IAC 39, LV8 33, maf 4, O2 50-650 all values at idle. The other coil pack that I replaced had only 2.1k ohms of resistance. I am developing a pull your self bald syndrom.
car running very rich
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charlloots
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adjust your fuel pres the weather is changing did you change your fuel filter ?
What AF meter are you reading the "rich" from?
It sounds like you have a scan tool....what was the knock retard...and the O2 millivolts at WOT? What are the BLM's and INT's doing. If the BLM is real low (90) it means you're rich...the computer is taking out fuel.
At WOT the mixture ~should~ be rich. Even the "target" 780 millivolts O2 at WOT is "rich" compared to stoich 14.7:1.
What did the plugs look like when you took them out?
I'm not saying that you're wrong, it's just that the bucking may be caused by something else.
BTW Cold air will make the car run leaner....the computer will compensate. You'll see the INT's go up above 128 and if the INT's stay high long enough they will also pull up the BLM's. You really shouldn't have to make drastic changes to your fuel pressure when the weather turns cold.
Code 42 is Electronic Spark Timing error...you may have knock something loose when you changed the coil pack...or the module may be going bad.
HTH,
John
It sounds like you have a scan tool....what was the knock retard...and the O2 millivolts at WOT? What are the BLM's and INT's doing. If the BLM is real low (90) it means you're rich...the computer is taking out fuel.
At WOT the mixture ~should~ be rich. Even the "target" 780 millivolts O2 at WOT is "rich" compared to stoich 14.7:1.
What did the plugs look like when you took them out?
I'm not saying that you're wrong, it's just that the bucking may be caused by something else.
BTW Cold air will make the car run leaner....the computer will compensate. You'll see the INT's go up above 128 and if the INT's stay high long enough they will also pull up the BLM's. You really shouldn't have to make drastic changes to your fuel pressure when the weather turns cold.
Code 42 is Electronic Spark Timing error...you may have knock something loose when you changed the coil pack...or the module may be going bad.
HTH,
John
It sure sounds like you're not getting a good spark. Do you have another ignition module you can try/borrow?
You might separate the coil pack from the module and make sure the wires are still OK. The best thing to test your ignition is Casper's coil pack tester, but I don't even have one of those....they're not too expensive if I remember correctly. But, that doesn't do you alot of good right now.
I haven't ever had any ignition problems, so I can't be of much help. Here is the info on you're code 42.
http://www.gnttype.org/maint/malf.html
http://www.gnttype.org/maint/malf.html#42
The conditions for setting this code are:
System in BYPASS mode but the ignition module is still controlling timing
- or -
Engine speed > 600 RPM with no EST pulses (ECM controlled timing) going to the ignition module for 200 msec.
Typical causes for this code include:
1) BYPASS line is open or grounded
2) EST line is open or grounded
3) PROM or CALPACK not seated properly in the ECM
4) Poor connections between ignition module and ECM
5) Poor routing of EST harness and/or poor quality ignition wires (EMI induced electrical noise)
6) Faulty or incorrect ignition module
7) Faulty ECM
You might go thru this list and try to find the problem.
Good Luck,
John
You might separate the coil pack from the module and make sure the wires are still OK. The best thing to test your ignition is Casper's coil pack tester, but I don't even have one of those....they're not too expensive if I remember correctly. But, that doesn't do you alot of good right now.
I haven't ever had any ignition problems, so I can't be of much help. Here is the info on you're code 42.
http://www.gnttype.org/maint/malf.html
http://www.gnttype.org/maint/malf.html#42
The conditions for setting this code are:
System in BYPASS mode but the ignition module is still controlling timing
- or -
Engine speed > 600 RPM with no EST pulses (ECM controlled timing) going to the ignition module for 200 msec.
Typical causes for this code include:
1) BYPASS line is open or grounded
2) EST line is open or grounded
3) PROM or CALPACK not seated properly in the ECM
4) Poor connections between ignition module and ECM
5) Poor routing of EST harness and/or poor quality ignition wires (EMI induced electrical noise)
6) Faulty or incorrect ignition module
7) Faulty ECM
You might go thru this list and try to find the problem.
Good Luck,
John
IAC values shouldnt have much to do with whats going on.
From your symptoms these are the possible culprits that I can think of :
Have you tried swapping out the ECM ?
Ign module, also check the connector to module and make sure wires/pins are okay. Ive heard of some people having problems with the connection here.
Also, what shape is the timing chain in ?
ECM would be the 1st thing I would try, easiest too. Ive had code 42 before, and problem was the ECM. Ive gone to the junkyard and gathered a few spares that have come in handy. Also, this bucking youve mentioned, is there popping/backfiring from the intake? Make sure boost is down while you are trying to track down this problem just to cancel out the possibility of a detonation/KR problem here.
Just my .02 cents. Good luck.
From your symptoms these are the possible culprits that I can think of :
Have you tried swapping out the ECM ?
Ign module, also check the connector to module and make sure wires/pins are okay. Ive heard of some people having problems with the connection here.
Also, what shape is the timing chain in ?
ECM would be the 1st thing I would try, easiest too. Ive had code 42 before, and problem was the ECM. Ive gone to the junkyard and gathered a few spares that have come in handy. Also, this bucking youve mentioned, is there popping/backfiring from the intake? Make sure boost is down while you are trying to track down this problem just to cancel out the possibility of a detonation/KR problem here.
Just my .02 cents. Good luck.
The error 42 code is gone since I disconnected Direct Scan. The car actually runs pretty good, but without Direct Scan I can't see what is going on. Before all my problems FP was set at 41 psi static, but now anything over 31 psi static is rich (via ATR A/F gauge). I am still running the same amount of boost as before, which I thought I would go lean at 15-17 psi boost but it is almost rich. 
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