Terrible Rough Idle, Good MPG = *BLOWN SC gasket*..pics pg 2
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Joined: Jul 2004
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From: Twin Falls, Idaho

could this possibly be something related to a faulty cam sensor but not throwing a code? I'd think if that was the case I'd have a screwed up idle at 1200+ too.
I'm guessing MAF or IAC...to start. If those are swapable between a 2000GTP i can swap in my garage and test. if I recall the 98'* maf sensor was different.
maybe even a failing EGRvalve that has not gotten to the point of throwing a code?
what else would be just at the low RPMs? it does not sound like a misfire at all, it is just "lumpy" to try to desribe it..I can get a video.
I dont like throwing parts to guess but I'm having a hard time finding a similar case on the SEARCH here.
Its dropping about 200 rpms 2 times a second...just shakes kinda but is smooth while it does it.
I'm guessing MAF or IAC...to start. If those are swapable between a 2000GTP i can swap in my garage and test. if I recall the 98'* maf sensor was different.
maybe even a failing EGRvalve that has not gotten to the point of throwing a code?
what else would be just at the low RPMs? it does not sound like a misfire at all, it is just "lumpy" to try to desribe it..I can get a video.
I dont like throwing parts to guess but I'm having a hard time finding a similar case on the SEARCH here.
Its dropping about 200 rpms 2 times a second...just shakes kinda but is smooth while it does it.
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From: Twin Falls, Idaho

Originally Posted by willwren
Please stop editing the topic title so we know it'* the same topic.
Have you done anything suggested yet? No sense asking more questions until you do.
Have you done anything suggested yet? No sense asking more questions until you do.
Yes the MAF and IAC has been cleaned.
Ok..you checked the maf and IAC, done most of the tune up and it'* still acting like a vacuum leak. Give this a try.
Also.. remove the coils and test the primaries as well as the secondaries (I believe you've tested the seconardies already?)
Originally Posted by BillBoost37
Spuds...after reading your ride post on the new car. I'll have to suggest that in fixing up all the leaks and issues. You may come across the problem or at least be able to rule out many items.
Then you should have SAID that you did that.
Plugs and wires were replaced 'awhile back'. Pull them and check them. Did you clean the IAC passage in the TB and clean the TB itself? Check the coils as suggested. These are all the 'normal' things you do on high-mileage cars.
Plugs and wires were replaced 'awhile back'. Pull them and check them. Did you clean the IAC passage in the TB and clean the TB itself? Check the coils as suggested. These are all the 'normal' things you do on high-mileage cars.
Thread Starter
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From: Twin Falls, Idaho

First thing I do with any new car is clean the throttle body and clean the TB sensors regardless of age or miles. This was the first thing I did, I then changed the plugs, and wires, this was done on Sunday.
The TB was amazingly clean for the age and miles, It was much cleaner than my 93 was.
next step is to check the primarys, I will do this and check back.
I also hope to get my hands on a IAC and MAF sensor, and swap on. I'll do the other troubleshooting first though.
The TB was amazingly clean for the age and miles, It was much cleaner than my 93 was.
next step is to check the primarys, I will do this and check back.
I also hope to get my hands on a IAC and MAF sensor, and swap on. I'll do the other troubleshooting first though.
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Joined: Jul 2004
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From: Twin Falls, Idaho

Originally Posted by sonoma_zr2
did you get my pm, will that maf work for you?





