Misfire issues
Thread Starter
Joined: Feb 2007
Posts: 1,446
Likes: 0
From: Tampa, FL
Misfire issues
Ok, so about two weeks ago I have my #2 coil pack go bad. Threw codes and I had a Misfire on #2 & 4, as well as random misfires. Got a new coil pack, dropped it into #2 and switched around the other three. I also got brand new NGK plugs. Earlier this week I got some misfire, but no CEL. I pinpointed it to idle only, and it was more noticeable when the fans kicked on and even moreso if I had the A/C on, with both at the same time it was surprising I didn't have a light yet. I cleaned the IAC and the throttle body. Well, last night while idling, the light came on. It is not a consistant misfire. I'll be idling along fine and then for 2-3 seconds it will get rough and then be fine. There is not pattern other than it hangs around more consitantly if the A/C is on and the fans are on together, but even then it goes away and comes back, and again there is not pattern. I had the CEL checked and it is misfire on #4. 
I never misshifted in the car, just hit the rev limiter in third once. Could I have bent a valve? Here are the reasons I found while searching (different thread and the OP had misfires on all 4):
I went through three half tanks of Shell, BP and Hess to see if it could be gas, but that wasn't the case. (This was over the course of the week). Can anyone help? I am going to get a bottle of fuel system cleaner and see it that "loosens" anything in the injector up. Just for info's sake:
Its an AP1 with 56k miles and I change the oil on a set schedule and the consumption is at a quart or less between intervals (3000-3250 miles).
I know its alot of reading, but I am hoping someone has an answer.
I never misshifted in the car, just hit the rev limiter in third once. Could I have bent a valve? Here are the reasons I found while searching (different thread and the OP had misfires on all 4):
Some causes of misfire, others can chime in to add to this...
Bad gasoline
Dirty fuel injectors (lean misfire)
Coil packs (not likely since you have all four misfiring)
Worn spark plugs (you changed these already)
Bent valves (check with compression leak down)
Bad ECU (have heard of one case)
Coolent leak into manifold or cylinder (water in oil? coolant low over time?)
Bad gasoline
Dirty fuel injectors (lean misfire)
Coil packs (not likely since you have all four misfiring)
Worn spark plugs (you changed these already)
Bent valves (check with compression leak down)
Bad ECU (have heard of one case)
Coolent leak into manifold or cylinder (water in oil? coolant low over time?)
Its an AP1 with 56k miles and I change the oil on a set schedule and the consumption is at a quart or less between intervals (3000-3250 miles).
I know its alot of reading, but I am hoping someone has an answer.
Joined: Feb 2008
Posts: 3,171
Likes: 0
From: Jax. Florida
just a guess .. but did you gap your plugs correctly?
nevermind.. I saw that you had the problem before new plugs... hmmm.
and I would not think you would have a bent valve from hitting the rev limiter a few times.
nevermind.. I saw that you had the problem before new plugs... hmmm.
and I would not think you would have a bent valve from hitting the rev limiter a few times.
Thread Starter
Joined: Feb 2007
Posts: 1,446
Likes: 0
From: Tampa, FL
I did, but nothing seemed to be the same issue as me. If you know of a thread, please link it.
Edit: tried different search terms and ended up with the answer that I need to check my injectors. I will try this and hopefully it solves my issue.
Edit: tried different search terms and ended up with the answer that I need to check my injectors. I will try this and hopefully it solves my issue.
Thread
Thread Starter
Forum
Replies
Last Post