Misfire Issue

[HyperHawk]

Ok, so I just got done changing 2 spark plugs and all 6 wires. I start the car up and it is now rumbling and misfireing regularly. I scanned it and its throwing a P0420 cat code, and a random cylinder misfire code. Could it be an o2 sensor throwing off the car causeing it to misfire. Anything else it might be?

[firebirddrvr]

Re: Misfire Issue

check the coils and icm

[Leonard 3.8L]

Re: Misfire Issue

Coils...

[HyperHawk]

Re: Misfire Issue

so upon further inspection turns out one of my wires fell out, and burnt. Changed it and its no longer rumbling but still has an occosional misfire under harder acceleration.

How can I test the coils to see if they're bad?

[Leonard 3.8L]

Re: Misfire Issue

Change one and you'll know.

[HyperHawk]

Re: Misfire Issue

Change one and you'll know.

im not gonna buy one if I dont need it

[Leonard 3.8L]

Re: Misfire Issue

im not gonna buy one if I dont need it

If you have meter you can check it.

[firebird19_99]

Re: Misfire Issue

i have a quick question, what does a misfire feel like when driving?

[HyperHawk]

Re: Misfire Issue

i have a quick question, what does a misfire feel like when driving?

The car stutters and shakes and feels like ur losing alot of power, idk really how to explain it more then that

[firebirddrvr]

Re: Misfire Issue

take the coil off and take it to your local auto parts store and they will be able to tell you whether or not its bad. take all of them in along with the icm and have it all checked while your at it

[Leonard 3.8L]

Re: Misfire Issue

It will sound like it's running on 5 instead 6 cylinders.

[firebirddrvr]

Re: Misfire Issue

It will sound like it's running on 5 instead 6 cylinders.

it will feel like its running on 5 cylinders instead of 6, and you probably will not have a very crisp throttle response either

[Leonard 3.8L]

Re: Misfire Issue

it will feel like its running on 5 cylinders instead of 6, and you probably will not have a very crisp throttle response either

Same thing. It will feel like it's about to stall out.

[firebirddrvr]

Re: Misfire Issue

yep and your idle may jump around a little bit....not sure if weve mentioned that one yet or not haha

[HyperHawk]

Re: Misfire Issue

So my idle is fine car stopped rumbling and shaking and runs right most of the time but i'm still getting the bad throtle responce under acceleration. Though the ses isn't flashing