Cylinder misfire at idle

[87Superdupra]

So I just got my car back from the shop after getting a diag. done and I'm told one of my cylinders is not firing at idle. This is strange because It seems like my exhaust would sound like shit, Yes? This could explain the fuel stains that my exhaust leaves at idle but why would a cylinder not fire at idle, anybody had this prob before?

 

[robeats91t]

I've got a rough idle that developed when I changed plugs recently. While I had the upper intercooler piping off I noticed that there was considerable oil leakage from the valve cover gaskets--I wiped it up and tightened the valve covers slightly (I'm always afraid of cracking the valve covers or stripping the threads in the head) and installed the new plugs.

Almost immediately I noticed a harsh idle, a stumble, especially when warm. I pulled #1 and #6 since they're easiest to get to, and #6 had been fouled up by oil.

This is only one of many possibilities, but check for oil (or water) around the plugs, and also check the condition of your wires. Also, if the coilpacks have been removed recently, ensure that the grounding strap from the coilpack mounting plate is connected to the head.

Hope this helps some!

 

[87Superdupra]

I changed my plugs recently and there was oil on the back plug. I guess I'll change my plugs and wires again but the comp. test I guess will tell me If anything severe is wrong. Man that would be fuckin sweet if it was just plugs or wires.