Hi, I'm new. I have an 89 civic that I've started having some misfire issues with. It basically started when the ECU threw a water temperature sensor code. I reset the ECU and the code hasn't come back for about 600 miles, but it started misfiring. It will only misfire once it's completely warmed up, and it will only misfire at low throttle positions (maybe 10%) and it's worse when accelerating.

Please help, I'm driving to Nevada next week (2000 miles) and I want the car to make it.

 

May be your car got too hot and you blew your headgasket...did you check the code or just throw it out...a code normally comes on for a reason, erasing it doesnt erase the problem... Collant in the cylinders = bad

 

Doesn't the TW code mean the sensor is going out, or there is a problem in the circuit? There isn't any evidence of water on the dipstick. The coolant gauge never goes above 1/2 way. I forgot to mention that I took of the IACV/EACV and cleaned it out and I've run some sea-foam through it, but niether seemed to fix it.