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Overheating!

Hello. I have a 1994 Honda Accord. About six months ago we noticed that it started over heating. However, it only occurs after driving for over half an hour and once I hit stop and go traffic. Then the engine themometer shoots up over half and heads straight to the top of the meter. But when I started driving again, it almost plummits back down and then occurs again when I stop (even at a stop light for only a minute or two). Please help!

From you description you could have malfunctioning radiator fans, a caked up radiator and/or engine block (too much scale and crud). I would check the cooling fans(s) first. The car is 16 years old and unless it has been maintained religiously, the cooling system could be clogged up, preventing rapid heat transfer. The thermostat should also be checked out.

If you give us the complete maintenance history we will be able to help you better.

Describe “top of the meter” Does it go all the way to the peg does it show how hot it is using some meaningful measure like degrees F ?

Is the indication on the meter the only indication of a problem? When was the last time the coolant was changed? Has the radiator and or cabin heater core, ever been cleaned?

At idle your car should engage a pair of electric fans to push cooling air to your radiator. If these fans are not working, your engine will overheat quickly when the car is running but idle. Warm the car up and open the hood to see if the fans are operating while the car is idling. If not, check the fuse for the fans, and if that is not the problrm, take the car in.

Low coolant, not in the jug but in the radiator is 1 possible source. It usually correlates to a leak and lack of pressure. A pressure test can help but make sure the radiator is full of coolant.

A plugged radiator wouldn’t act like that. It is almost certainly a fan problem. If you have working a/c do the fans run when you turn on the a/c? If the fans don’t come on when the temp goes up check the fan relay, there may be a similar relay in the car you can swap it with.

Fix It ASAP Or Park It ! If It’s Actually Overheating Then You’ve Possibly Damaged The Engine Or Are About To Damage It.

Get it checked and fixed immediately if not sooner. Your next trip could be your last trip.

How does the car’s Heater work ? Does the air temperature vary from hot to cool with the swings in temperature indications ?

As Waterboy suggests, you should check the coolant level in the radiator (full ?) and reservoir (full cold mark ?) WITH THE ENGINE COLD, if you haven’t done so already.

CSA

Ya sure get alot of hoopla in here…Id start with the (Fan) and (Thermostat)