The car overheats when moving, but not when sitting still. The head gasket has been replaced, as well as the thermostat, water pump, and of course the water pump gasket. There are no leaks anywhere in the system. The coolant system appears to have no blockages, and the thermostat appears to be working properly. While driving, the car overheats and the radiator boils over. Also, the fan does not turn on, but the fan relay is good, as well as the appropriate fuse, and the fan itself tested out fine. The radiator has no blockages. I am at a loss as to what is causing this. Any ideas?
2006-09-12 10:15:24 · 6 answers · asked by Anonymous in Cars & Transportation ➔ Car Makes ➔ Honda
The fan not working might be related to the issue, but that is not causing the overheating. When moving, the fan does virtually nothing. I ran a car without a fan completely for a few weeks because the fan was on backorder, and the only time the temp would start to creep up would be when sitting still. This car is only overheating when moving.
2006-09-12 10:26:14 · update #1
replace the radiator if it has plastic tanks and aluminum core [metal radiators can be rodded out if the core is still in decent shape]
2006-09-12 16:33:39 · answer #1 · answered by hobbabob 6 · 0⤊ 0⤋
If you mean the coolant system has no leaks because there is no coolant on the ground then I suggest you do a leak down test on the coolant system. Pressurize the radiator and see if it will hold pressure. You can also have the coolant tested for combustion byproducts as well to determine if hot exhaust gases are getting into the coolant. Whenever I've seen that problem, the coolant looked particularly nasty though and I could see bubbles/foaming in the coolant as it passed under the radiator cap.
A compression check would be helpful too.
Now I will tell you of a little odd personal experience I am having with a Mitsubishi 3000GT of mine... It has EXACTLY the same symptoms as your car. The problem turned out to be excessive loading of the engine by way of the AC compressor. The compressor belt would squeal a lot so we tightened it up until it stopped squealing... sure seemed tight though... tighter than any other belt I've ever adjusted. Everything worked though so I ignored it. However, the AC compressor was actually siezing up and getting harder and harder to turn which represented a huge load on the engine. When we came to a stop and the engine was idling, the heat from freeway speed rpms was gone and apparently the cooling system could dissapate the heat and the temperature went down. Now we run with the AC off until we can get that compressor changed out and all is normal.
Make sure you don't have any internal leakage that can go undetected and check into the loads on the engine.
Good luck!
2006-09-12 23:37:52 · answer #2 · answered by Les 4 · 0⤊ 0⤋
Perform a "block test". This test checks to see if there are hydrocarbons entering your cooling system. If its positive, you are looking at big money to repair. Negative results indicate that it is something other than the engine itself that's causing the overheating. Your fans not coming on is also a problem, although it may not be the cause of your overheating. Some of the things you wrote is questionable. Contact me, I can help you fix it. The block tester can be bought at NAPA.
2006-09-13 03:27:35 · answer #3 · answered by Anonymous · 0⤊ 0⤋
luckily for me when i replaced my head gasket on a different car, it solved my problem........ but what it sounds like to me is, and i hate to tell you this , is a crack in either your head itself or the engine block. from the exhaust ports into the water ports. that would deffinitley give you high temps and make it boil over. at idle, it won't get as hot because the coolant system is just barely abile to keep up with it. at speeds it gets really hot, so it boils.
2006-09-12 17:35:47 · answer #4 · answered by shreck 2 · 0⤊ 0⤋
I had a similar problem and it turned out some idiot at the dealership wired my fans backward when they were working on it, so the fans actually ran backwards, blowing hot air out of the engine instead of cool air into it.
But it sounds like your fans aren't working at all. If the fan doesn't work, the car will overheat, period. Sounds like a wiring issue to me. Make sure the thing is plugged in too. It sounds stupid but sometimes we overlook simple stuff.
2006-09-12 17:22:59 · answer #5 · answered by Rainier 5 · 0⤊ 1⤋
sounds like u still have a leak from your combustion chamber into the cooling system...did they shave the head? use an updated gasket?.....is it a honda thermostat? some aftermarkets dont always work correctly with a honda...
2006-09-13 08:22:22 · answer #6 · answered by Steven S 3 · 0⤊ 0⤋