Yet another overheating problem....

[Whrutty]

Hey everyone,

I have a huge overheating problem with a 01 Honda Civic EX. The engine will overheat after being on the highway and then slowing down (like in traffic or normal driving). I checked the fan relay and fans which both work. The odd problem is that the fans will run inconsistently (the fans will turn on with A/C but then turn off while sitting still). Also when the car begins to overheat and the heat is turned on, the heat will work for a period of time after which the air becomes cool and no longer hot. There is no white smoke and there is no loss of coolant. I don't believe it to be the head gasket but I could be wrong. The thermostat and coolant were all replaced/flushed etc. which did not help the problem. I haven't tried changing the thermoswitch.

Any suggestions would be great.

Thanks

 

[lowlife9]

what about the water pump or there could be air bubbles in the system.

 

[TAZ_FERIO]

Sounds like a headgasket to me. Same thing I had going on this summer, works fine 45+ then when slowing down starts overheating. I didnt notice any white smoke either. Take it to honda and they can do a chemical test to tell you, takes about an hour or so.

 

[Whrutty]

what about the water pump or there could be air bubbles in the system.

I want to say that there are no air bubbles in the system as the problems were there before and after all the fluids were changed/flushed.

Sounds like a headgasket to me. Same thing I had going on this summer, works fine 45+ then when slowing down starts overheating. I didnt notice any white smoke either. Take it to honda and they can do a chemical test to tell you, takes about an hour or so.

Did you notice any loss of coolant with the headgasket bad? Any ideas about how much does a headgasket would run if done at shop and not a stealership? I was REALLY hoping it wouldn't be that....

Would keeping the fans shorted out all the time make a difference for a quick fix for the time being (wouldn't keep it that way long) or with a bad headgasket would it still overheat.

 

[cheezeonmakneez]

Hey everyone,

I have a huge overheating problem with a 01 Honda Civic EX. The engine will overheat after being on the highway and then slowing down (like in traffic or normal driving). I checked the fan relay and fans which both work. The odd problem is that the fans will run inconsistently (the fans will turn on with A/C but then turn off while sitting still). Also when the car begins to overheat and the heat is turned on, the heat will work for a period of time after which the air becomes cool and no longer hot. There is no white smoke and there is no loss of coolant. I don't believe it to be the head gasket but I could be wrong. The thermostat and coolant were all replaced/flushed etc. which did not help the problem. I haven't tried changing the thermoswitch.

Any suggestions would be great.

Thanks

I would look into the coolant temp sensor. if the engine is as hot as it registers and you have enough coolant, you should have more heat then you need.

 

[Whrutty]

I would look into the coolant temp sensor. if the engine is as hot as it registers and you have enough coolant, you should have more heat then you need.

I thought it very odd that the heat would get super hot and then just cut out to cool air. I have never had that happen on any car that I've had where a radiator went or thermostat etc. Where is the coolant temp sensor located? I found thermoswitch (located just after the thermostat)....is that the same thing or are there two sensors??

 

[TAZ_FERIO]

Once I fixed the thermostat the coolant didnt go down or anything, the simple answer to your question is to take it into honda and have them do the chem test. Personaly I got so sick of not knowing that the problem with my car was I was more then happy to pay whatever it cost to have honda figure it out.

 

[jonathan2006]

change the oil out and see if it has water in it
ive blown 2 headgaskets
the first time was obvious the second time was not until we started to drain the oil out and saw the water was mixed with it at the bottom of the pan

 

[dj_cronic_metal]

Yours sounds a lot like what happened to mine. Do yourself a favor and go to an autozone and get a compression tester. Check the compression on each cylinder should be between 185-139 I think is the right range. If you have a cylinder that is off compared to others then it could be the head gasket. While your there pickup a kit to flush the radiator, and a new thermostat. I doubt this would be your ect sensor. If you want to bypass the compression tester find a shop or get someone with a leak down tester. A leak down tester will tell you if the head gasket is bad or not. the compress loss shouldn't be above 20%. I got charged 40 bucks for a leakdown, but all the time it saved me knowing what my problem was after hours of overheating trouble was worth it.

Also so you know your fans should kick in at 170-180 degrees right about the time that your thermostat opens. What you can also do is run the car till it hits operating temperature. 170 degrees. Check the top radiator hose and then check the bottom radiator hose. If both of them are the same then the thermostat should be opening. If the bottom is colder than the top after that period of time then your thermostat would eb the problem. Hit me up if you need help.

 

[toneekay]

So after reading all of this, checking your sensors, and your cooling components, and you're still having this problem... Check out your head gasket. I would have to say this is your problem with a 60% chance.

I've had the exact same symptoms on my car and turns out I had a crack in my head gasket around one of the guides.