LS doing strange things...
AcidReiyne
10-13-2006, 10:27 AM
Hello, I have a 2002 LS V8 and have never had a single problem with it...until now.
The other day I was on the interstate doing about 70mph when a car pulled out in front of me and I was forced to step on the brakes extremely hard. As soon as I got up to speed again the car was shaking slightly and the check engine light was on.
The next day there was no problem, no check engine light and no shaking. Today however while going down the highway the problem started back up and the check engine light came back on. I parked the car, and had no issues for a while but later on the same slight shaking occured again while driving but this time with no check engine light. I noticed a somewhat burnt smell when I got out of the car but upon opening the hood, smelled nothing. The smell was primarily inside the cabin.
I know that my air conditioning filter needs changing, but I doubt that would cause any of this--I think. I also noticed that in addition to the shaking the car seemed to lose speed and shift strangely (automatic) when I was close to home. Then again, this could have been my imagination since I was primed for problems.
I have an extended warranty but before I put it into action I'd really like some experienced imput on this. The one thing I have to have is a dependable car. Thank you so much.
(Oh, and the car currently has 65,000 miles on it)
The other day I was on the interstate doing about 70mph when a car pulled out in front of me and I was forced to step on the brakes extremely hard. As soon as I got up to speed again the car was shaking slightly and the check engine light was on.
The next day there was no problem, no check engine light and no shaking. Today however while going down the highway the problem started back up and the check engine light came back on. I parked the car, and had no issues for a while but later on the same slight shaking occured again while driving but this time with no check engine light. I noticed a somewhat burnt smell when I got out of the car but upon opening the hood, smelled nothing. The smell was primarily inside the cabin.
I know that my air conditioning filter needs changing, but I doubt that would cause any of this--I think. I also noticed that in addition to the shaking the car seemed to lose speed and shift strangely (automatic) when I was close to home. Then again, this could have been my imagination since I was primed for problems.
I have an extended warranty but before I put it into action I'd really like some experienced imput on this. The one thing I have to have is a dependable car. Thank you so much.
(Oh, and the car currently has 65,000 miles on it)
shorod
10-13-2006, 01:46 PM
Well, you may want to stop by your local chain auto parts store. They should be able to pull the stored diagnostic codes from the PCM to tell you what the car though the problem was which caused the illuminated Check Engine Light (CEL).
I suspect you will find that the code is for a cylinder misfire, like P030x where x is the cylinder number the misfire was detected on. This has been a very common problem on the earlier LS, although not so much on the 2002 and newer. However, that would fit your symptoms.
What happened on the earlier LS was the valve cover gasket spark plug well gaskets would leak and allow oil into the spark plug wells. After enough of this oil pooled up, it would cause the ignition coil in that plug well to short through the oil to the head rather than through the spark plug to the head.
The fix for this was a new gasket set (and there is a revised design, although most 2002 models would have the revised gaskets) and a new coil for the effected cylinder.
Maybe the abrupt stop sloshed enough oil around to start the short circuit, and then the carbon track was formed which allowed it to continue to short and misfire. Or, maybe it was purely coincidence. Or, maybe your issue is not a misfire afterall. Getting the code read will be one step closer to determining which scenario you are experiencing.
-Rod
I suspect you will find that the code is for a cylinder misfire, like P030x where x is the cylinder number the misfire was detected on. This has been a very common problem on the earlier LS, although not so much on the 2002 and newer. However, that would fit your symptoms.
What happened on the earlier LS was the valve cover gasket spark plug well gaskets would leak and allow oil into the spark plug wells. After enough of this oil pooled up, it would cause the ignition coil in that plug well to short through the oil to the head rather than through the spark plug to the head.
The fix for this was a new gasket set (and there is a revised design, although most 2002 models would have the revised gaskets) and a new coil for the effected cylinder.
Maybe the abrupt stop sloshed enough oil around to start the short circuit, and then the carbon track was formed which allowed it to continue to short and misfire. Or, maybe it was purely coincidence. Or, maybe your issue is not a misfire afterall. Getting the code read will be one step closer to determining which scenario you are experiencing.
-Rod
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