So if you've been following along my 05' GTP has had some issues with going into boost, losing power when trying to accelerate at a higher rate of speed. Under normal driving conditions I was pulling 15* Kr just moving to 30 mph and under 10"Hg. Then around 3-6* just maintaining speed. Then it magically stops and I might .1*-.3*. Then nothing sometimes I can ease on the throttle and get to 5psi then it will drop to .1psi (the ECU seems to open the bypass) I haven't checked Comanded TP verses actual to see if the throttle is being limited as well. Timing will go to -15*. I watched the O2 go dead lean once and let off.
things I've done.
removed the gauge from my fuel pressure gauge and added an oil pressure sender in order to moniter fuel pressure from inside the cabin slightly more safely. Pressure holds at a constant 65psi all day everyday.
monitered those above items plus MAF cfm and have as high as 1,990 cfm at about 8psi (sometimes it will run decent for a second)
plugs and wires Autolite 606 coppers gapped to .050"
no misfires
went from 3.4 that came on the car to 3.6 and changing to 3.8 tonight (Thanks Casper00693)
Cleaned MaF and TB.
tonight I was on the way home and got on it while watching timing, didn't go full throttle but about 3/4 accelerating from a 20mph roll then engine layed over and timing went to -15*, the engine was not in boost 0 on the gauge and .3psi on T app. Then everything went south traction control went off reduced engine power popped up on the DIC, I went pulled into a parking lot barely, the engine was running real rough and looking at the O2 it was dead lean and timing was fixed at -15*. I started pulling codes in this mode before I shut it off and restarted. Well in the few minutes
It took to do this I noticed smoke starting to pour from the right side of the engine under the hood. I shut it down and did get a P0068. I popped the hood and the smoke was coming from the rear of the engine. When I looked it seemed it was the exhaust overheating -15*+dead rich makes for some very high EGT's. So after sitting for a few minutes I fired it up again and drove of as if nothing happened. Hope I didn't cook the Cat.
my theory is bad knock sensor for one (be nice to know which) don't know if the ECU will freak if I disconnect one or both.
as far as the P0068 I am wondering if the 3.6 is causing more airflow than expected. The output seems proportional cruise is about 230cfm idle is about 50-65cfm.
I'm stumped what do you guys think is going on.
Thanks,
Jeff
things I've done.
removed the gauge from my fuel pressure gauge and added an oil pressure sender in order to moniter fuel pressure from inside the cabin slightly more safely. Pressure holds at a constant 65psi all day everyday.
monitered those above items plus MAF cfm and have as high as 1,990 cfm at about 8psi (sometimes it will run decent for a second)
plugs and wires Autolite 606 coppers gapped to .050"
no misfires
went from 3.4 that came on the car to 3.6 and changing to 3.8 tonight (Thanks Casper00693)
Cleaned MaF and TB.
tonight I was on the way home and got on it while watching timing, didn't go full throttle but about 3/4 accelerating from a 20mph roll then engine layed over and timing went to -15*, the engine was not in boost 0 on the gauge and .3psi on T app. Then everything went south traction control went off reduced engine power popped up on the DIC, I went pulled into a parking lot barely, the engine was running real rough and looking at the O2 it was dead lean and timing was fixed at -15*. I started pulling codes in this mode before I shut it off and restarted. Well in the few minutes
It took to do this I noticed smoke starting to pour from the right side of the engine under the hood. I shut it down and did get a P0068. I popped the hood and the smoke was coming from the rear of the engine. When I looked it seemed it was the exhaust overheating -15*+dead rich makes for some very high EGT's. So after sitting for a few minutes I fired it up again and drove of as if nothing happened. Hope I didn't cook the Cat.
my theory is bad knock sensor for one (be nice to know which) don't know if the ECU will freak if I disconnect one or both.
as far as the P0068 I am wondering if the 3.6 is causing more airflow than expected. The output seems proportional cruise is about 230cfm idle is about 50-65cfm.
I'm stumped what do you guys think is going on.
Thanks,
Jeff
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