Flashing "Service Engine Soon Light" when under hard acceleration
Just today I was driving my car when having to pass someone to get on the interstate I had to punch my SSEi pretty hard. I've had to do this many times and for the first time today when doing this the car started to putter or misfire. At the same time my Service Engine Soon Light blinked until I let off of the accelerator and then it stopped. Any ideas on what this might be?
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From: Windsor, Ontario / Detroit, Michigan









Senior Member

True Car Nut
Joined: Sep 2006
Posts: 4,816
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From: Windsor, Ontario / Detroit, Michigan









Same with mine, except on cylinder #5. I was able to determine it wasn't firing by using a mechanic'* stethoscope. Plugs, wires, coils, then injectors ... that'* the order in which I would try to diagnose a misfire.
Thanks guys. I actually just changed my spark plugs and it ran fine for about 3 days and then this started happening. I'm probably asking a stupid question now, but based on the recommendation of checking the plugs/coils/cables, what could I have done that would cause this? I was always under the impression if I possibly over cranked a plug and cracked the porcelain that I would be hearing a loud pop when I'm driving, which I am not. Also, I put in the GM recommeded plugs, AC Delco, however I did not change the wires, just the plugs.
Last edited by Hesk000; Oct 22, 2009 at 11:19 AM.
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True Car Nut
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From: Windsor, Ontario / Detroit, Michigan









There is always the possibility of a bad plug, but I would look at the wires. When were they last changed? Check wires and coils. Instructions are in this thread:
https://www.gmforum.com/t278818/
https://www.gmforum.com/t278818/
Joined: May 2006
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From: Sheboygan Wisconsin






It'* always possible you have a bad plug out of the box. Another possibility is do you have screw on tips on the plugs? Some times these get loose and cause a misfire.
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From: Indianapolis, Indiana

"Clogged catalyst, if plugs/wires/coils don't fix it. I'd bet my left nut on it."
LOLOL!!! Im a little disturbed wit how quickly this cat offered up his left nut.LOLOLOL!!! Hilarious bro!
LOLOL!!! Im a little disturbed wit how quickly this cat offered up his left nut.LOLOLOL!!! Hilarious bro!



