Thread: misfiring issues 05 grand prix GT L26

Yesterday my CEL starting flashing and my car was misfiring, exhaust was sputtering, lots of vibrations at idle, complete lack of power when driving, and a foul smell of gasoline from the exhaust. The CEL is now steady. My scanner isn't working so I'm taking it to the shop tomorrow. I just wanted your opinions. It's at 178xxxkm and due for an oil change and spark plugs/wires. The symptoms seem like spark plugs or wires, maybe coil packs, or a clogged cat. What do you guys think?

Also yes I know there's not much you can guess without the codes, I'll find them out tomorrow I'm guessing I'll have a cat code and misfire code.

sounds like a clogged cat, if the tune up dont help id look there next.

well my scanner is working again. All I pulled was P0300 Powertrain - Multiple Cylinder Misfire

that code is cause by the need for a tune up, or a clogged cat, both will make the cel flash too.

so start with the tune up, if that dont fix it, its most likely the cat.

the shop is telling me that it's the ignition control module and the spark plugs and wires all tested fine. Coil packs tested fine as well but they think one of them may fail when it starts to get hotter outside (it's about 6 celsius today and it was high 20's all week)

icm could be the problem as well. get a junk yard icm, and swap it in there, unless the shop still has it and you going to pay them for a new one.

used is far cheaper tho. its a few small bolts job, 20 minutes tops to change.

I would do it myself or get a junk yard part but I'm away at school right now (no junkyards within bussing range) and actually need my car by tomorrow to get back home. I let the shop do it, albeit paying through the roof for the part ($475)

ouch. this is why i dont like shops.

im sure if you bought one from advance auto on line with a discount, and say you need to buy some tools, you'd still be way ahead of that 475.

ahh but I'm in canada so it would be part source which would be similar to OEM price ($375...the shop is making some money which they have the right to). And yeah even if I bought it OEM and did it myself I'd be way ahead as I'm still getting charged labour and diagnostic

i hate being in a pickle.......but we do what we must do.

got the car back, runs great. Exhaust sounds like I'm catless now though. Could be the holes in my muffler, but my exhaust was never this loud. It's droney, backfires, and has a deep rumble. Did I shoot my cat? lol

it's a giant hole in my muffler...resolved