I have a 2005 Honda Civic that is overheating. We have changed the Waterpump, Thermostat and the radiator, but I am still having problems.

What is odd is that it doesn't happen every time. I drove it about 15 blocks on Sunday and on the way back it started to overheat. So I took it back to the mechanic, he drove it without any problem so I went and drove it for an hour and the heat never went up. But this has happened a couple of times now and I am certain that at some point in the near future it will get hot again.

The only thing that I have been able to find is that tells me anything is the fan only seems to come on when the air conditioner is on even when the car is hotter than it should be but the car has overheated while the air conditioner is on so the fan itself doesn't really seem to be the problem.

The coolant is full and I haven't had to add any, the oil and coolant both look normal to me and I haven't seen any smoke or other signs of the Head gasket but I'm still considering a test if that seems likely because I use my car at work so I need it to be reliable so simply waiting until it happens again really isn't a good option.

Any advice would be helpful. Thanks.

 

Have you had the head gasket checked? I think it's causing the problem.

 

I've done what I know to check it, which is basically looking at the coolant and the oil and watching for smoke. None of which seem to shows signs of that, but I know there are more conclusive tests and if it seems likely that it is the head gasket I'll ask them to run the actual test.

 

Can you jump the fan connector at the thermostat housing and see if the fan is powering on? Have you replaced the radiator cap? Any extra fluid in the overflow than what you normally saw in the past?

 

The 05 I believe can get a cracked block. It may be under warranty still. Google it and check the front of block behind exhaust manifold.

 

all cars with aluminium blocks can crack or warp under excess heat and a 05 is definitely not still under warranty.