rough idle
Thread Starter
Instructor
Joined: Sep 2011
Posts: 106
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rough idle
ok starting my third summer of ownership of my 99 a4, last summer was noticing the slightly rough idle becoming more rough than usuall so ichanged plugs and plug wires (38,000) mile car by the way just in case something that simple might help, no real change, cleaned throttle body...no real change, didn't clean maf just because I didn't know a thing about it, ran a bottle of techron through it about a month later, still rough, overall performance off idle is ok I guess for a 273 gear a4, so now what? also I didn't disconnect the neg battery lead when I cleaned throttle body should I reclean that and maf with neg disconnected to let it relearn with them clean?
also sent pcm to east coast super chargers for mail order tune which did wake up the car when I hammer it but didn't affect roughness of idle as far as I can tell, last thing I can think of is I run 93 octane all the time and put full bottle of stabil in then fill tank and drive a mile or 2 before storage so I don't think im screwing up fuel system with old gas
also sent pcm to east coast super chargers for mail order tune which did wake up the car when I hammer it but didn't affect roughness of idle as far as I can tell, last thing I can think of is I run 93 octane all the time and put full bottle of stabil in then fill tank and drive a mile or 2 before storage so I don't think im screwing up fuel system with old gas
Thread Starter
Instructor
Joined: Sep 2011
Posts: 106
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Le Mans Master
Joined: Feb 2012
Posts: 6,644
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From: OK
Burning Brakes
Joined: Jun 2010
Posts: 1,014
Likes: 5
From: Rockwall TX
You might check your plug wires in case one came off ( don't ask). I replaced mine and one came off? This was after a bit of time, so it did not even occur to me to check them.
But, doesn't really sound like your problem.
But, doesn't really sound like your problem.
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Melting Slicks
Joined: Nov 2008
Posts: 3,146
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From: Edmonton Alberta, Canada
If you just got it out of storage give it a few days running and see if that helps. (I also own a Chevy SSr) it runs rough for a few days after taking out of storage then slowly smooths out.
Thread Starter
Instructor
Joined: Sep 2011
Posts: 106
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cleaned maf and tb last night even though they both looked really clean, just went for a 2 hour ride, still a bit rough but not as bad as yesterday...ill try more techron when I get rid of the old fuel, I did disconnect neg terminal just in case that's the proper way to do it on vette, I know the forums ive read on my truck suggest that but not sure if all pcms function the same, also was looking for cracks or soft vac lines as suggested