SES light and weird idle
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Launching!
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From: Sweet home Alabama
SES light and weird idle Ok I just got a 02 z28 a4 not too long ago. All has been good so far until today...
I got in the car and drove to work no problem. I was sitting at a stop light on the way home and noticed that it was idling around 5-600 rpms and felt kinda rough. The SES light came on right before I pulled in the driveway. What's most likely the culprit? I guess I'll have the code scanned tomorrow and see if I can track it down. Just wondering if anybody has had a similar problem( I'm sure somebody has). Oh and btw sorry for such a noob question it's just bugging the hell out of me right now. Thanks.
I got in the car and drove to work no problem. I was sitting at a stop light on the way home and noticed that it was idling around 5-600 rpms and felt kinda rough. The SES light came on right before I pulled in the driveway. What's most likely the culprit? I guess I'll have the code scanned tomorrow and see if I can track it down. Just wondering if anybody has had a similar problem( I'm sure somebody has). Oh and btw sorry for such a noob question it's just bugging the hell out of me right now. Thanks.
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From: Sweet home Alabama
Oh yeah forgot to post that the light just stays on. It does not blink. I'm glad it's not that I saw in some other posts that the blinking ses is a engine misfire. I'll post up tomorrow see what I can come up with.
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From: Schiller Park, ILL Member: #317
It can still be a misfire without flashing, but flashing means a severe misfire.
FYI, sounds like your idle rpm is right where it should be. Stock idle speeds for all LS1s '98-'02 are as follows:
A4: 650rpm in P/N, 550rpm in gear
M6: 800rpm
FYI, sounds like your idle rpm is right where it should be. Stock idle speeds for all LS1s '98-'02 are as follows:
A4: 650rpm in P/N, 550rpm in gear
M6: 800rpm
Get the code read at autozone. They will tell you what the problem may be. My car always idles at 500-600 RPM even when it was Misfiring severly(SES light flashing) last friday it was at the same RPMs just vibrating alot...and when i would giv it a quick rev it wanted to cut out...Went to the gas station and filled up and idk y but the misfire was gone...either solved the problem or it was just coincidence and the misfire might come back later. Car is running good right now though.
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Launching!
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From: Sweet home Alabama
Ok the code is the catalyst system below efficiency. Of course, I don't wanna replace the cat or cats bc I planned on doing long tubes in a month with my bonus check. ****, hopefully it's just a 02 sensor? Damn..
Never heard of a post cat 02 causing a rough idle. I'd also put my money on a plugged cat...
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From: Sweet home Alabama
Teching In
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I've been through this a bunch of times with several different types of cars. It's usually not the cat. Most likely culprit is the o2 sensor (probably the rear or post cat) or a vacuum leak. Since you cleared the code and it's running good the cat should not be plugged up. Good Luck
I heard about this too. And I also heard that if it is due to the cats and there is a recall you can go to the GM dealer and possibly get them replaced free of charge. Theres no harm in driving over there and asking them. Good luck.
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Launching!
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From: Sweet home Alabama
Yeah I believe the post cat driver side 02 sensor is the culprit. Yeah I'm going to get my tuner to turn those off after I get long tubes. Running fine today turned over the tires going into second today and it's an A4 lol. I love this car damn!
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From: Sweet home Alabama
Ok turns out it's the driver side cat is plugged. Gm said I was good on time but my mileage is over...uggggghhhh! just hit a 100k. They said the cats are only cover for 8 years or 80k miles...
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From: Schiller Park, ILL Member: #317
Do you have a visual or sniff test in your state? If not, ditch those cats and never look back. If you have an OBD scan test, any good custom tuner can fix you up to still pass that test without cats....or you can use O2 sims.