joncan

My 2005 civic has previously blown a head gasket (or should I say I blew it by not turning it off in time while it was overheating) for this very issue. It has gone the entire summer not acting up at all I guess because it was warmer. We are in the north tn area and It just recently got cool for a couple of days about two weeks ago and it started doing the same thing again.

What is going on is that the fan is not turning on in time. It will get really hot before it does and I have to shut it off. This ONLY happens when it is cool outside. Somehow it is messing with the sensor. We have replaced multiple parts that they assumed were the issue and thought it was fixed until two weeks ago. Then it got warm out again and my car's been in the shop for two weeks because they 'can't get it to act up.' Any suggestions? I'll answer questions and adjust post accordingly.

ezone

Is the radiator low? That's when the problems happen. Fill it to the top and burp the system good, problems go away for a while until it gets low again.




Head gasket is blown again? Something leaking coolant?

joncan

No. The fluid was/is fine and there's no check engine light or anything that would show it being the gasket. The fan will eventually turn on but most of the time not until it's too hot and you have to turn it off to cool it down. And it only happens when it's cold outside.

joncan

ok so it happened not in the cold weather. the temp gauge jumps up to VERY hot and when i turn the car off (still flying down the road) and turn it back on it almost immediately, most of the time, goes back down to normal temp without the engine light coming on and no other signs of anything happening. thoughts? I don't know about honda civics specifically but in my (very little) research I'm guessing it could be the thermostat (which was just changed) the coolant temperature sensor (which might be the same part? but seems to be different in some cars) or the computer itself.

04 blue civic

Is the radiator full?

is the overflow filling up if coolant is low?

Any coolant on engine, battery, etc spraying around?

Is the car actually overheating? Meaning did you ck the radiator hoses for one hot one very cold?

Can you hear the coolant “boiling”?

If the coolant temp sensor was bad it would likely set a etc. as well as usually run like crap due to computer not getting correct reading and overloading fuel..


Just an FYI mine did same exact thing and was head gasket. Breached between cylinder three on exhaust side to coolant jacket.