2002 Honda Civic EX coupe. 234,000 miles.

I’ve been dealing with and chasing this issue for years. Somehow it has not blown up…yet.

Sometimes I can drive the car for weeks at a time with no indication of overheating and then all of a sudden, the temperature gauge just goes nuts. Jumping up and down all over the place. Sometimes it creeps up and then levels back off. Other times it violently pegs out to full hot, stays there for a while and then comes back to normal.

I have checked the relays & fuses…good. I’ve jumpered the fan control switch…good, fans work. Water pump has approximately 34k miles and good flow is evident when I have the radiator cap off with the engine at operating temperature.

Today(05/18) I installed a new OEM Honda thermostat and also replaced both temperature sensors for the fans and temp gauge.

Then I bled the coolant system of air for approximately an hour, installed a brand new radiator cap and went for a test drive.

I made it about 140 miles before the temperature gauge once again starts to act-up.

Got it home, popped the hood, got my infrared thermometer and started watching…with the temperature gauge staying approximately 3/4 to full blown HOT, the temperature on the upper hose stayed around 225°F and the lower hose would creep up to around 205°F before the fans cycled on and then the temperature of the lower hose would drop to around 185°F before the fans shut off.

Does anybody know if these temperatures are normal?

Am I possibly dealing with some weird intermittent wiring issue that’s causing the temp gauge to have a mind of its own???

Any insights or advice would be greatly appreciated.

 

I have a 2002 Civic Si. The temp gauge on it goes about 1/3 of the way up and never moves up or down. I have the Torque app: Just out of curiosity I hooked it up through a bluetooth adapter to the OBDII port. I could then see the actual temperature warming up and going up and down while driving.

I suggest you do something similar to see if your temp gauge is not reading correctly.