Coil Pack or Spark plug issue-started idling rough this morning...
08-22-2006, 04:48 AM
#1
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Coil Pack or Spark plug issue-started idling rough this morning...
This morning on my way to work I downshifted to pass someone and got on it when the power fell off dramatically. It felt like it overboosted and cut the power like I have felt before. I back-peddled in the middle of the pass trying to get it to "reset" but that didn't work. After the pass the check engine light started flashing and the car was running rough. If I let the car idle the check engine light would stop flashing. After a few more minutes the car seemed to idle a little bit rougher and the check engine light stayed on then continously. The exhaust had the catalytic rotten egg smell. Could this be a plug that went bad or a coil pack that has given out suddenly? It feels like its running on 3 maybe even 2 cylinders. My car is an '01 225QC with 58k miles. I have never changed the plugs nor has the dealer.
08-22-2006, 05:11 AM
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Sounds like a coil pack failing
The flashing cel and rotten egg smell are caused by the fuel not igniting in the cylinder with the bad coil. If you don't take care of it soon you risk the chance of damaging the catalytic converter.
Although at 58k without a plug change, they should be done now anyway.
Although at 58k without a plug change, they should be done now anyway.
08-22-2006, 05:17 AM
#3
sounds like a coilpack. if you are away from the house or dealer, you should check
under the hood and disconnect the injector plug for the bad coilpack cylinder. this way, you can drive the car with rough idle and no power without dumping unburnt fuel down your catalytic, thus, destroying it.
to tell if the coilpack is bad...with the car idling, disconnect one injector plug at time...if the idle is worse, that means that cylinders coilpack is good. if the idle doesn't change when you remove the plug for the injector, that coilpack is bad.
leave the plug off the injector, once you find out which cylinder has the bad coilpack...drive to the dealer, buy a new coilpack or two and replace. with than many miles on the car, i'm surprised that you or the dealer have never replaced the plugs. i would remove the plugs and see what they look like.
to tell if the coilpack is bad...with the car idling, disconnect one injector plug at time...if the idle is worse, that means that cylinders coilpack is good. if the idle doesn't change when you remove the plug for the injector, that coilpack is bad.
leave the plug off the injector, once you find out which cylinder has the bad coilpack...drive to the dealer, buy a new coilpack or two and replace. with than many miles on the car, i'm surprised that you or the dealer have never replaced the plugs. i would remove the plugs and see what they look like.
08-22-2006, 05:39 AM
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Exactly what I had with bad coil packs, twice. Rough idle, flashing cel when accelerating....
rotten egg smell. Don't drive it, that rotten egg smell is unburnt fuel going to the cat. You could disconnect one coil at a time and note changes, the one that dosen't make it run worse would be the failed coil.
08-22-2006, 06:06 AM
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Thanks for the obvious way to test! I'll have to test when I get home...
I figured the same thing with the smell and the way it was running and did worry about messing up the O2 sensor or the Cat due to unburnt fuel. My ride this morning was only 10 minutes so I hope I didn't mess anything up in that time. I babied it home but did start it a few more times listening for things. How bad am I going to get nailed on a coilpack? What consensus on plugs lately, best ones?
