weird idle
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From: Indianapolis, Indiana

Ok so I spoke to soon. On my way home from work my old friend "SES" showed up again. I replaced both the IAC and the PCV,(had a credit on my rewards card)and the ses light is still on and the car still shakes at idle.I'm stumped.
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Took the car in to get smoke tested on friday. Everything checked out. No leaks. Also had fuel pressure checked. It was at 42 psi. I was told 45-55 was normal but 42 was acceptable. Hooked car up to diagnostic machine, got no response from MAP sensor. Even unplugged it and nothin happened. I mean shouldn't the car have died? Anyways replaced the MAP and what do u kno, still runin lean still shakin at idle. Diagnostic said pcm keeps tellin engine to run lean but then it richens back up when I get on throttle. Possible bad 02. The battle continues....
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Ok guys update time. Turned out my engine was not likin the 42 psi that my fuel pump was runnin. installed a new pump and fuel pressure is back well within the suggested psi. now my oh crap moment. discored a leak at the base of my supercharger. the new pump although it made the car idle a whole lot smoother didnt completely solve my p0171 issue. so i was randomly spraying carb cleaner, hit the base of the SC right inbetween 2 of the injectors and i heard the idle change. looked a little closer and the zzp gasket that was on there has a bit of overhang, it was enough to keep it sealed during the smoke test but twhen i pulled it down a little and sprayed, definite leak. so needless to say got a sc gasket change comin up here soon. HOPEFULLY this will resolve the issue. im goin on a full month here dealin with this thing. I'll post pics of the engine when im done, thing looks brand new with all the new parts she'* gotten tryin to fix this thing. keep u posted.
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From: Indianapolis, Indiana

Ok so time for another update. So the last time, my mechanic friend had found a leak under the supercharger gasket. (Still waiting for the new gasket.) Anyways today i took the car for an alignement. Can someone please tell me why after the alignement, the engine light went off and the car now drives better than it has in months? now let me preface this by saying that every time prior to this that the engine light went off, the car would continue to run like crap(weird idle and what not) and eventually the light would return. also as it has been runnin lean my fuel economy has been through the roof. however this time, the light went off, the idle smoothed out and my fuel economy has gradually dropped back to what it was before this whole nightmare began. now im no idiot so i know the alignement didnt caue this new revelation, but you gotta admitt that the timing is pretty amazing. now i should also mention that thursday i changed the throttle position sensor. however after the install it still ran rough and the light was still on. likewise prior to the alignement the light was still on and it was still running rough. i have to say this has been the most bizzare code i've ever dealt with on any car. like i said still got a new SC gasket comin and since i've already paid for it, still plan on goin through with the gasket swap. as for right now she'* running pretty good. i have no idea what to make of this. let me know what you guys think.
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Hopefully this will be my final up date on this issue. Last time i was talking about doing a supercharger gasket swap. well that has finally been done. have a look at what we found.

GAsket looks pretty much shot, but thats not even the best part.

yes that is a rip in the gasket. No clue how it got there, but i do know it wasnt there when i put it in. Im thinkin when i had my accident, my car was left at a pretty steep incline(sideways) dont know if it is possible for some coolant to have overun the LIM and swamped the gasket, (only thing i can think of) and made it all soggy.
anyways the projecty was a success. No more rough idle, but more importantly no more P0171. heres a few pics of the engine bay all put back together and with new valve covers. the rear cover had been leaking for a while so i finally decided to knock it out while the engine was in pieces.


GAsket looks pretty much shot, but thats not even the best part.

yes that is a rip in the gasket. No clue how it got there, but i do know it wasnt there when i put it in. Im thinkin when i had my accident, my car was left at a pretty steep incline(sideways) dont know if it is possible for some coolant to have overun the LIM and swamped the gasket, (only thing i can think of) and made it all soggy.
anyways the projecty was a success. No more rough idle, but more importantly no more P0171. heres a few pics of the engine bay all put back together and with new valve covers. the rear cover had been leaking for a while so i finally decided to knock it out while the engine was in pieces.






