alright so im pretty framiliar with hondas, ive had my fair share, got a deal on this 01 civic, 1800 bucks the other day, has an overheating problem, i desperatley need to fix it to use as my commuter because currently i am driving a half ton truck that gets 13mpg.

first off the radiator fan doesn't turn on on its own, i am going to try to get a new relay and fan switch, can anyone tell me which relays those are b/c in the fuse box it just has pictures and im confused lol

so ive been driving around with the AC fan on (this keeps both radiator fans turning) and the car still gets hot (doesnt quite overheat), and goes up for a minute maybe, then back to normal temperature, sometimes it doesnt even get hot at all, the coolant is full, the previous owner had a new radiator and hoses installed.

the other thing that happens is when the car gets hot, the heater stops working? and when it goes back to normal temp the heater works again?

i drove the civic on a two hour trip yesterday, didnt have any problems on the freeway, but when i was 5 minutes from my destination (probably goin 20mph the car got a little hot. then on the way driving home (had the ac on the whole way) the car kept getting pretty hot for a minute, then cool back down every couple minutes or so, and was doing that heater thing?

could this be the thermostat? i was told the waterpump was done 5k miles ago, but no paperwork, im hoping its not a head gasket because that would be a bitch lol, could it be a bad temp sensor? anything helps, thanks in advance

 

I would start with fresh coolant, a thermostat and thermostat gasket, and if it's cheap... a temp sensor.

 

start with a thermostat since it's easy, but it sounds like you have a blown hg. exhaust gases are pressurizing the coolant system and preventing it from circulating properly. on my old car i had the exact same thing happen to me, pretty much to a t, and the head gasket was the culprit.

 

I am having an overheating problem too. 1989 civic LX sedan, 186K, manual trans. Timing belt, new water pump, thermostat replaced less than 500 miles ago. Car drives 10 miles and begins to overheat. Turning heat up, fan on high, will reduce heat for a moment, but then it goes right back up. Please help, unemployed, money is an issue. What could I do to troubleshoot?

 

you can also try flushing out your rad and your whole cooling system.

 

first start with the fans...my guess is its the fan switch/temp sensor. cost like 15-20 bucks. that will turn the radiator fan off and on. when youre going 20 mph the air doesnt pass through the radiator as well as when youre going 67mph or something like that LOL. bleed the coolant system again after and make sure your fans cycle on and off while idling. check the radiator hoses after its warm to see if they are both hot....this would mean the thermostat is not stuck and working properly. you could also put a block tester on the radiator to detect exhaust gasses in the coolant system. rent it for free at auto zone. if you have exhaust gasses in there you have a blown head gasket of cracked block. its most likely just the head gasket though. but my guess is its the fan switch. they almost never get replaced regularly (every 60,000 miles). most people think they never go out or since it works why fix it. then they take a trip somewhere far from home and it goes out in BFE and its a saturday and no parts store locally to BFE. preventive maintenance is best so replace the fan switch every 60,000 miles. the electronics on cars today are weird. temp sensors stop stuff from working normally. possibly why your heater trick stopped working after it got too hot. i know if the car is too hot and you turn it off it wont start again for like 30 minutes after it cools off a little and the temp sensor allows the ecu to operate again...crazy huh? try the fan switch first

 

new head gasket.

 

Change the thermostat and all the coolant. it sounds like you have air in the cooling system. Be sure to burp the system when you do this.

This is a conmen problem that people over look and over think.

 

nah sounds like a blown headgasket. sorry man. on my 89 my car was overheating... wtf no white smoke no blue smoke... losing coolant? wtf.... no leaking hoses. come to find out after i wrecked the car it was the headgasket. the water ports in the gasket nearest the dulley had rusted thru into #1 cyl and was causing all issues.

 

Sorry man. You advice comes 4 years too late.