calling on the oil-fired pros here:
inb4 UVCH (possibly)
some details:
96 f250 7.3
ex. cab. short box
tony wildman tuned (chipped removed for diagnostics)
gauges
straight pipe
200K miles
Here's my issue, my pickup started up and drove to work fine this morning, then on my lunch break it started up fine, but when i hit the throttle it revved up (normally), then on deceleration it started running rough.
so I turned off the motor, and started it back up; and everything was normal, except when i revved the motor, and again it started running, and idling rough. giving it throttle didn't help.
however, here's the kicker... after 5-15 seconds of idling rough, it quit the rough idle and returned normal. i figured out that if i rev the engine and return to normal idle slowly (instead of letting my foot off the throttle), it wouldn't act up.
like i said earlier, i removed the chip before i did any work, i know they can cause issues if the contacts on the pcm aren't cleaned good enough. but I've had the chip for a few months now.
so far, ive taken the valve cover off, disconnected both the wire harnesses, plugged them back in, and put everything back together. and it runs fine now.
basically my question is to you guys is that what do i need to fix this? should i just replace the wire harnesses?

sorry for my broken thought, im still a little shaky.


ps: i dont know if it matters or not, but my pyrometer is set up on the passenger side exhaust manifold, and when it was running rough my egt's didnt go up at all. they stayed at the ambient temp.

 

A lot of times rough idle is caused by bad connections threw the valve cover. Both the under cover harness and the outer harness connector can cause the miss. Check both ends for burned pins, and/or melted plugs. You can use a multi meter to ohm the gasket and harness.