98 Honda Civic Engine Overheating?

[K-Oz]

My girlfriend has been having overheating problems with her car. The problem has been going on for about six weeks. Some people suggested that maybe it needed another thermostat or radiator. Well, she ended up getting both, a new thermostat and radiator... the problem was still there. Her father recently took the car and kept it for a week, but when he had it, the car never did overheat one time. He then took it to friends of his, who are mechanics and they couldn't find a single thing wrong with the car. Though, they couldn't find anything, they claimed that it was possible that some sort of air (or air pocket) was in the system when one of the parts was replaced and had probably worked its way out. So, when she gets her car back, the car's temp would go up and down within 3-4 days of getting it back.... going as high as three-fourth of the way toward "H" (hot). Now her car is back to touching "H" again as of this morning.

I was wondering do anyone here know what else the problem could possibly be?

Thanks!

 

[ash]

maybe its neither one of those... i drive a pontiac and i had that problem but i really did need a new radiator but later it started doing that again and come to find out it was just my gages messing up and needed my dash replaced

 

[High Tech Redneck]

Since the thermostat had been replaced, several other things need to be checked. If this car has an electric fan on the radiator, make sure the fan motor is running when the car gets hot. You can run 12VDC straight from the battery to the fan to test it manually. The fan also has a relay switch. Usually near the Driver's side firewall area under the hood.

If the fan is working, then let's check the Anti Freeze level and flow. With the motor cold and off, take the radiator cap off and start the motor. Go and watch the Anti Freeze in the Radiator filler cap. Within 10-15 minutes after the motor warms up and the thermostat opens up, you should see the fluid circulating well. If the Anti Freeze level drops several inches or out of site when the thermostat opens up, then the fluid level is too low and you need to add anti freeze to within one inch of the top of the filler neck. Do not add water, this will dilute the anti freeze and cause a boil over from pressure.

If the anti freeze does not circulate, since the thermostat has already been replaced, then the water pump may be failing. Water pumps have rubber impellers that wear out, gears, etc.

If none of this appears to be a problem and it only seems to overheat with your girlfriend driving, maybe it's in her driving habits or her route. If she drives in heavy stop and go traffic, with the Air Conditioner on, up and down steep hills or mountains, etc. then overheating is a problem.

I would guess the factory thermostat in this car and the one replaced was rated at 180 Degrees. If everything looks okay otherwise, then consider replacing the thermostat again, but with a 140 degree or lower thermostat. This will open up more quickly to pump the coolant through the motor at a lower temperature. Make sure she has a clean Air Filter. Dirty filters restrict the air flow in the engine and make it produce more heat.

Are any of the air cowlings or ground effects missing or damaged? Most people don't know that the air flow from that plastic thing under the radiator or front bumper does have a purpose beyond looks. It scoops up air to circulate around the motor to help with cooling also.

If all else fails, install a manual switch for the fan she can turn on from inside the car. Wire it to a switched circuit (One that only has voltage with the key on) so if she forgets to turn it off when parking, it will go off when the key is off. Some cars you may hear the cooling fan running even after the car is turned off. This is normal until the engine cools below the thermocouple temperature range for the fan to switch off.

It sounds like you found a crooked shop that sold her a radiator and thermostat without ever actually diagnosing the problem.

Sometimes older cars may have defective gauges or circuits giving a false reading. Take a regular meat thermometer, and when you see the Anti Freeze flowing in the radiator opening, stick it in and read the temperature. It should be between 140 and 180 degrees. If the gauge inside has a higher reading, then the gauge or the wiring is faulty. Be sure to wash the meat thermometer before you use it on the steaks.....Anti Freeze is a deadly poison, even a few drops.

Good luck, and watch out for the crooked mechanics in the future.

 

[Dtownfb]

Technically, the car has not overheated. It simply is running hotter then normal but something is making this happen.

I would have the mechanic do a pressure check on the cooling system. You could have a blockage in the cooling system or it could be a bad seal on the radiator cap.