Will do.

 

Tightened bolts, cleaned connections, no change. Attached video

 

What sensor tells the computer you’re at operating temperature? Because it runs great hot, could that sensor be stuck at “hot temp” and telling computer to adjust fuel to operating temperature fuel mixture? Would the computer even notice that the wrong input is being received, so no CE light? Just thoughts

 

The coolant temperature sensor. What is the digital temp reading?

 

Warm 189f, is this what the computer is seeing? If so I need to compare cold with oat right?

 

Your thermostat should open at 180 degrees F and go to as far as 190 F and close .

Your cold temperature should be ambient temperature

 

Ok, this morning I turned the ignition on and checked temp with oat, it matched. I cranked up engine and it ran great! WTF over…

 

Fingers crossed it’s working fine now.

 

Good chance following Oldblue’s advice about tighting the fuse panel’s bolts paid off. How old is the battery? The onset of cold weather can unmask a weak one. Low voltage combined with weak electrical connects can cause computer problems resulting in U codes, although I have no idea what U0100 means.

Glad it’s OK now. Maybe it’ll stick. Maybe your car needed a few cycles to sort things out. 11% ethanol is normal if you’ve been pumping E10. What do they sell in your area? In many places gas retailer need to change their blends seasonally, which can contribute to a/f problems.

What about the P0700?

 

It’s back again. 42 degrees this morning, same issues. Finally got car to stay running and watched digital water temp gauge. At 140 all misfiring stopped and engine smoothed out.