So I pulled some codes today at work and have a #2 cylinder misfire. Heres the story everynow and then in summer mornings I will start my car and it will trip the engine light and i will smell what i think is gas for a second, but will run fine and go off in a day or so. Here in Ohio we just broke 60 degrees in the dead of winter soooo....My engine light came on again one morning but this time has stayed on for three days. It ran ok at first and over the next two days it feels like i am running on 4 cylinders only. On a side note my car usually starts right up in the morning but will be very choppy the first minute or two but never usually trips the light. Should i replace the wires, cap, and rotor? doesnt sound like theres always luck there i keep hearing about the fpr. Is that under the plenum on mine or in a more convenient location? Thanks!

2000 Blazer 4x4 206k
40k on rebuilt trans.
138k on new used motor.
No death cool (Ethlyne Glycol)

*Also did new plugs 3 years ago but think everything else is stock.

 

If the cap, rotor and wires have not been changed in that amount of miles, they are certainly due... Can't say if that's your problem, but I'd say it's likely. The easiest thing to do is pull the cap and see what it looks like inside. You can also look for spark arcing from cracked insulation on the wires. This is easier to see at night. Try spraying water from a spray bottle along the wires while the engine is idling. If the idle changes or sparks occur when you spray a certain area, you need wires. The plugs could also be fouling from unburned fuel.

If the problem is always in a particular cylinder, that suggests a bad wire. If it moves around, or you get the dreaded P0300, it could be the cap & rotor, coil, or too much play in the distributor gear.

Note that I haven't even touched on possible fuel system causes...

You need to start somewhere, so I'd look at the cap & rotor and check the wires first. If that's the cause, change the plugs too while you're at it.

 

Much appreiated. Can anyone tell me where the pcm is also?