I have a 2004 Saturn Ion with about 189,000 miles. Recently the car has been running very hot when AC is on and the car is idling or in traffic. When I stop for about 30 seconds ill hear something click on, the AC will start to blow warm air, the engine will heat up and the car has a tendency to jump forward. When I start driving again the AC will cool off but the engine takes a while to cool back down. When it jumps forward, the RPM’s shoot up and it jumps forward about a foot. I recently had it inspected and looked at by a mechanic, but this was over the winter when there was no need to use the AC.
How high does the temperature gauge read?
It depends on how long I idle, usually about half way up to the 3/4 mark, but a few times in real stop and go traffic I have had the warning light come on because it was all the way up.
If it is heating up in stop and go traffic, one possibility is the engine fans aren’t coming on when they should. Or they may come on, but don’t spin fast enough. They usually only come on if stop and go traffic or when the AC is on. I’ve had a similar problem on my Corolla three different times, once it was a wire became disconnected that powered the radiator fan, the other two times the coolant temp switch that turns the radiator fan on had gone south.
You hear a click and notice warm air coming from the AC vents? hmm … well, it might be an engine-saving technique. The computer may automatically turn on the passenger compartment heater and blower to cool the engine if it thinks the engine may be overheating.
One frugal idea you could try on a flyer, replace the radiator cap. Sometimes they fail and the cooling system can’t hold the required pressure, which results in overheating.
In any event, this needs to be addressed diligently and quickly, otherwise you may be looking at expensive problems. If my car was doing this, I’d only drive it if the coolant gauge was at mid-point or below. If it went higher than that, and turning on the heater to max didn’t bring it down, I’d stop driving.
Open the hood and turn on the AC. If the fan isn’t running, that is the issue. Now you have to determine if it is the relay or the fan motor itself.
Another cause may be partially plugged radiator. If it is plugged internally, you need to have a mechanic determine whether it can be flushed out or needs to be replaced. If it is externally plugged then take a garden hose and from the engine side of the radiator, squirt through the radiator honeycomb to flush out the debris.
garden hose and from the engine side of the radiator, squirt through the radiator honeycomb to flush out the debris.
Some caution is in order with this technique. I’ve had problems on my truck using the hose-spray to clean the radiator where the force of the water spray bends the little fins over at a 90 angle and makes the air flow through the radiator problem worse rather than better. Suggest to try it on a small spot in the corner of the radiator first, then look carefully to see if the fins are getting bent.