Tom P
I'm Awesome
Yeah I'd really doubt it to be the coil. I hadn't really considered the effects of the trims. Did you try running with the o2s unplugged? That should throw it into an error state and keep it open loop, correct?
Ran them unplugged for about 4 hours worth of towing my travel trailer ~5000lbs. No change
Again though trims apply in open loop. If he could clear his trims then run open loop that'd give us a better idea. I have a Harbor Freight scanner that displays PIDs. That's what you're after. The ability to monitor ECT, IAT and **** like that.
Pardon my ignorance but could you explain PID, ECT and IAT?