Misfires

[Green Machine]

Upon accelertion, my engine misses alot. i just changed the spark plugs and the ignition coils too about 4 months ago. i got 185,000 miles on the engine. i know those coils couldnt have gone bad so quickly. what else could it be...?

[goldbar]

Re: Misfires

What year is your car? I have a '97 and in '99/early '00 there was a recall for engines with this issue. I haven't had any recurring issues with this since, none that a good spark plug change couldn't handle. Also, my car only has 85,000 miles on it, so maybe it's something to look into for the future.

You might want to see if your car has been serviced for something like this in the past.

[Vanquish]

Re: Misfires

What coils did you get?

My car had the same problem with coils going out and I kept replacing them with the brands that are sold at Autozone and sure enough, not even a month or two would go by and it would need changing again (there was a recall, but I didn't buy the car brand new so I figured I wasn't entitled to this recall).

Well, after about 4 or 5 changes of the same coil, I got fed up with it and went to a GM dealership and got a coil from them and put that on there and have never had a problem since.

So, if you did get a coil from a local autoparts store and that is your problem, save your time and money and go let a GM dealership know what is going on and ask them for one.

Also, what year and engine model is your car?

A few things that are usually the culprits of misfires are:
Fuel Filter is clogged and/or impurities in the fuel system
Faulty or incorrectly gapped spark plugs
Incorrect ignition timing
Defective spark plug wires
Weak or faulty ignition coils
Emissions system components faulty
Uneven cylinder compression pressures
Weak or faulty ignition system
Vacuum leaks at intake manifold or plenum or vacuum hoses
Dirty or clogged fuel injector

Good luck, and I hope you fix the problem. Is your SES light on? Even if it isn't, I would find someone with a scanner, even a local mechanics shop(though this will cost money) and have them put the scanner on and check out all these things listed above and make sure that they are working properly. I'm sure upon checking one of those things, you will find your problem.