01 ranger had a small oil leak a valve cover gasket. A friend of my nephew is a mobile mechanic. He came over and fixed it....I thought. Turns out he snapped a bolt stud and it leaked BAD. He came back and repaired it but then it misses at idle. Comes back and replaces the 02 sensors...still misses and stinks like rotten eggs. He said possibly a catalytic converter. I went to a muffler shop and they checked it....no code and has full exhaust.

I think maybe its in the wiring he had to move to get the cover off.

Thanks for any ideas...I'm lucky I have another truck to drive.

Sounds like your nephew needs better friends

be nice to know what engine. photo of the valve cover in question might help too. almost sounds like a crossed plug wire on a v6

Thanks spanky...I printed out firing order and waiting for cooler weather. I'm too old to get out in this heat. I also got a OBDII scanner.

Thanks spanky...I printed out firing order and waiting for cooler weather. I'm too old to get out in this heat. I also got a OBDII scanner. It's a 4.0L V6.

Also, check all of those vacuum hoses. All it takes is one cracked or unconnected hose to cause the engine to stumble.
Pop the hood early in the morning, temps aren't too bad till around 11:30-noon'ish.