Cylinder 1 Misfire
 

this problem went away for a few weeks and now its back. check engine light came on one day when i turned on the ac. i hooked it up to the code reader and got "Cylinder 1 Misfire". i did not change the spark plugs or cables the last time. any suggestions on what i should fix.?

thxs in advance...........:)

The easiest way to help figure out what is going on is to start by moving the cable to another cylinder. If the misfire moves with the cable that is your problem. If it does not move then move the spark plug to another cylinder and see if the misfire moves. Those are the two easiest things to start with. If that doesn't solve anything there are a lot of things that can cause a misfire. Let me know how you make out with the moving stuff.

when i pulled the plugs i see electrical activity. i pulled the 1st and the 5th and they both were active. any ideas?

I've had a coil pack fail resulting in a mis-fire. I found that by random chance, but you can move the coil that operates cylinder 1 to a different position, same as said earlier, see if the problem follows the coil or stays at the same cylinder.
In addtion, you said you pulled the plugs? Does the one in cylinder one appear worn differently then the others?

Another mis-fire I believe can be caused by a problem fuel injector not spraying fuel into the cylinder.

Unfortunately misfires can be caused by so many things. Without being in front of the car with you it is hard to say what it is. Have you moved things around to see if the misfire moves? Misfires could be caused by faulty injectors like said previously. There could be valve train issues.

Cylinder 1 was a real pain 2 get out but when I finally removed it I found that the little white piece inside the plug had crack. I changed them not even a month ago. I replaced it with a new plug and the problem stopped. I reset check engine light and now I'm rolling smooth. Thxs for the help much appreciated. Anyone have an idea why it went out so quick?

Glad it was that easy a fix. BTW - I hope those are not BOSCH plugs (those seem to suck in GM cars, stay away, stick with AC Delco if you can).

If it had a crack already you may have hit it when installing it. I am glad you found the problem.

The 1 in there now I believe is a bosch since we were just testing it out to see if that was the problem. I have an AC Delco on hand for whenever it goes bad.