Rep Power: 252

Hey guys so last night I overheated and had to be towed home. I just recently changed my termostat so I know its not that. I checked for leakes and any crimps in the hoses but all seems fine. I also have no heat, just blows cold air. I think my fans are not kicking in. When are they supposed to kick in? I put my a/c on and the work but I cant get them to go on. They dont go on when car overheats or when I put my heat on. So what can it be? *My coolant level is on max*

 
Rep Power: 242

i think its your head gaskets

 
Rep Power: 252

I was told that it could be the coolant thermostat. How would I know if its the head gasket?

 
Rep Power: 811

any white smoke out the exhaust, white deposits on the plugs, losing coolant slowly, misfires on a cold start that later go away, bad cylinder compression, low coolant system pressure? thats headgasket.

 
Rep Power: 252

Hmm no signs of it being the headgasket plugs are clean and it starts up fine. I think im going to replace the coolant sensor and take it from there ill see what happens

 
Rep Power: 252

Changed it still no luck keeps overheating and still no heat. Any more ideas?

 
Rep Power: 811

what about thermostat? could be that.

 
Rep Power: 0

since your not getting any heat sounds more like a water pump if it was a head gasket you should still get heat

 
Rep Power: 252

Changed the thermostat as well as the coolant sensor.. My next guess is the water pump. Any ways to test a water pump? If its the water pump should I try it or just bring it to a mechanic? I know I would need to do the timing belt too im around 80k ish anyway any feed back would be nice.

 
Rep Power: 252

ah yea I forgot to mention..I finally checked my upper hose (the one from the thermostat to radiator) and its bone dry nothing is pumping through it.. does this guarantee its my water pump? Once againa any ideas on how to test my water pump?

 
Rep Power: 0

Dude u got a blown head gasket prob. My car was overheating like that alot but never got too bad. Then i changed my thermostat and it got worse. I took mine to the dealership to get checked out and they gave me the bad news. Youll prob do better letting the honda dealership check it out and make sure it aint the head gasket. They replaced mine for free cause i still had powertrain warranty you need to check into that.

 
Rep Power: 252

There was air in the line.. I looked over the obvious.. too bad none of you guys mentioned it, but thanks for the thoughts guys

 
Rep Power: 0

hey i got an 2005 ex with the same problem how did you removed the air from the line?

i change the thermostat and the radiator switcher still overheating and and no heat
there is no radiator bleed valve for this year!

 
Rep Power: 811

with car sitting cold for a few hours, open the radiator cap and start the car. warm it up to operating temp by revving to 3k rpms. turn heater on full blast and keep the radiator near full. add more so you can see the air coming out. once bubbles stop coming out, turn the ac on and see if more air comes out. once most of the bubble stop, you can turn car off and replace cap.

 
Rep Power: 0

still didn't ..work how long are u suppoed to do it for..i did about 30 min each both ac and heater....i forgot to mention im boosting about 5lb...even ran the car without turbo still have the same issue...what can it be? after purging
out the line it did run a little longer before overheating...should i continue this procces again?
and when i start to overheat i accelerate real quick the it start to coolo down and heat start to come out again....sometime it doesnt work even i accelerate...???????????
and coolant is bursting out of the rev. coolant tank....????? leak somewhere????

 
Rep Power: 0

i gotta 05HFPCivicSE EX and i got the SAME problem with random overheating. i replaced the thermostat and gaskets too. i was wondering why the head gasket would affect losing coolant slowly? also if it was air in my cooling system would a radiator flush (since im over due for it anyway) solve this problem?

 
Rep Power: 0

I have the same problem right now, i keep losing coolant and the car eventually starts to overheat. I changed the thermostat and still the same problem. The fluid seems to be filling up in the reservoir tank and overflowing out of it. I didn't realize this is such a common problem. Any suggestions what to do next? I think theres quite a bit of people in this thread looking for some help.

 
Rep Power: 0

I had this happen to me a few months ago.
This sounds to me that the water pump is dead.
The coolant overflowing into the reservoir is the coolant overheating in the radiator and pushing it back into their. Either that or you have a warped head or broken head gasket (as the previous poster has stated).
I believe the manual states the water pump should be replaced every 120k miles or so.

To see if the head gasket is leaking (whether it be a cracked head, or what have you), one can detect to see if there is exhaust gases coming out of the radiator cap.

Anyway, good luck.

 
Rep Power: 0

I've go the same problem, 03 Civic EX (SI Canadian) with 75,000Miles (122,00KM). I might drive around fine for a month, and then all of a sudden it starts overheating again. I've had it serviced for this problem 3 times. First time, they said it was the oil cap and Charged me $110, second time, they said they couldn't find anything and charged me $60, third time I had them change the thermostat for $120, but that didn't help either. All three times they've bled and refilled the coolant.

Notes...

-Car has plenty of coolant each time. It actually seems to have quite a bit more in the overflow (went from the full line to now at the very top of the bottle) then it did when it was last filled.

-using the heater may have something to do with it. The last 2 times it has over heated has been the last 2 times I've used the heater (about 3 weeks apart). I know that it's coming when I have the heat on and it refuses to blow warm air.

-It heats and cools quite erratically once it's started. It will climb quite quickly, then fall, then climb again, then fall, then go all the way hot, then I park the car and let it cool. After i start the car again, it may stop doing it or continue doing it.

-I don't drive it hard at all.

I can't believe it's the water pump at 75,000 miles, I don't drive the car hard enough to screw the head gasket, this is annoying as all hell. Any way of testing the water pump?

 
Rep Power: 273

There's something somewhere that is causing the coolant to be pushed out into the overflow tank by expanding air in the system. When properly purged and with vacuum in the system, the overflow tank will get sucked down when the car is cool, and filled up by any tiny expanding air bubbles when hot. Unfortunately, if there's a vacuum leak you'll get air sucked in somewhere and that creates a ginormous air bubble that expands with heat and pushes out excess coolant.

Does the overflow coolant level recede when the engine cools down again?

Have you had the radiator pressure-tested?

I have heard of head gaskets leaking that don't exhibit classic head gasket signs - I had an 88 Camry v6 that I am certain had a blown headgasket, but no white smoke. I believe there is precedent to say that there are some headgasket blows that are pressure-dependent, i.e. the headgasket is retaining its integrity at atmospheric pressure, but at operating pressures it fails, releasing exhaust gases into the system and causing non-traditional head gasket symptoms - since coolant isn't leaking INTO the cylinder, the engine isn't burning it, but the exhaust gases into the coolant loop would possibly cause a "no hot air" from the heater core.

Does it ever sound like running water or a river when you turn on the heater or start to get overheating?

More info would definitely help in a diagnosis.

 
Rep Power: 0

-The coolent level is back down to normal again today, and the first 2 of the 3 times I had the car in, I had the Rad tested.
-It's never made a running water sound when overheating, but I have heard (in the past seemingly at random times) a sound that would be similar to trickleing water, like water running in one of those cheap little desktop water fountains they sell. It would only happen in first gear at launch. This happened more frequently about 2 years ago, and hasn't happened much at all since I started having these problems last fall.

If there's an other helpful info I can give let me know!

 
Rep Power: 255

okay my car is currently in the shop because of everything you described. i dont know if it is that over heating that caused all sorts of problems, or if it is the blown head gasket, or maybe both combined to cause the problems. radiator at times was cold and heater at times blew cold. you need to get it checked out at the shop. turned out it was my head gasket, maybe caused by bad thermostat, or plugged radiator. had a compression test done and found the middle two cylinders were loosing compression... meaning warping head. im at 75K so decided just to change out everything. btw, i tried changing radiator fluid first time, but that was not the problem. get it checked out

 
Rep Power: 0

I drive an 02 ex coupe and my car has "overheated" since 03. I've had thermostats replaced, radiators replaced, all piping replaced, and the head gasket checked out. Every once in awhile it pushes the coolant out of the tank and the temp gauge goes from normal to hot to normal to red to normal. It's been this way for 5 years now and no one at any dealer has ever found the problem so it seems to be quite common in this generation of civic. I've never lost power though so I just let it go. my problems are with my tranny

 
Rep Power: 0

HI, i'm having a random overheating situation too. It overheats(blows coolant out the top of the reservoir cap) when I use the vtec ie over 4500 revs on the motorway, but is fine in everday town driving, even sat in traffic for 45 mins with no problems.

Anyone got a clue as to what iis the problem, (thermostat appears to be working as both rad pipes are hot) Honda said should change this plus the temp senseor as was running hot!