Mechanics

OVERHEATING

1999 Honda Civic

Engine Cooling problem
1999 Honda Civic 4 cyl Two Wheel Drive Automatic 170000 miles

My car starts running hot after I drive it for about an hour. I've taken it to a mechanic and they've hooked their scanners and gauges up to it and ran it for a while and it wouldn't start running hot and the scanner readings came back negative (nothing wrong). I've had the radiator cap, hydrothermal gauge, and one of the hoses replaced and it is still running hot after about an hour of driving (outside temperature is irrelevant). What could possibly be causing my car to overheat?
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Clblevins123
June 16, 2009.



Make sure the cooling fan is working.

It is also possible the temp gauge or sender is not working properly.

Hook up scanner to car and look at coolant temp reading on scanner and compare it to the gauge. If gauge is higher, then the gauge or sender is bad.

I would also change the thermostat and flush the cooling system as a general maint. Item.

Mmprince4000
Jun 16, 2009.
I don't have the equipment to do that myself so I'll take it to the mechanic and have him do it for me. Also, I've read online that it is possible for your car to start driving hot, and possibly overheat, because your water pump is going bad. Is that true? It is around, if not past, the time for me to replace the timing belt (and the mechanic said they change the water pump and such along with it). Could my running hot after driving for about 45min-1hr on the highway and then driving on side roads (30-40mph) be because of a water pump that's about to go out?

Tiny
Clblevins123
Jun 20, 2009.
It is possible the WP is bad, but generally they will fail at the seal/bearing and coolant will come out a " weep" hole cast into the pump.
Some pumps have a plastic impeller and these can seperate from the shaft internally causing reduced water flow.

NEVER drive a Honda if it has overheated, shut it off quickly.

Aluminum is very sensitive to heat and can warp if overheated.

Mmprince4000
Jun 21, 2009.