I replaced the thermostat and while it was about time to do so ( the gasket was non existant and the thermo old as dirt) it didnt solve my problems... My car still steadily increases in temperature as i drive it. I did notice that my fan doesnt comeone at 210 degrees and that I have to turn my AC on to turn on my fan in front of my radiator. Im also getting a coolant error on that system diognostic thing in the car... (its all digital). What should I do next? I was gonna replace my water pump but my neigbor said that the pump didnt look that old and i should replace these 2 sensors on the front of the block and the sensor on the radiator( for the coolant error, as i have plenty of coolant). Should that solve my problems? what else could it be?

 

Any ideas?

 

Sounds like a bad coolant temp sensor to me.
Especially if you are getting a fault code for it. First make sure your wire connection is good.

The computer reads the value of the sensor, when the reading hits about 220 degrees, it will turn on the fan until it cools down to about 190 degrees. Its safe to say your fan is working properly since it is supposed to turn on whenever you egage the A/C.

You can get one for under $20.



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92 Camaro RS, LO3, 5-spd, T-tops

Performance:
K&N Open Air Filter, Edelbrock performer TBI intake, Fastchip Prom, Timing +4 degrees, Centerforce clutch, Xact 8mm wires, SLP 1 3/4" Headers (coated), Flowmaster Catback Exhaust, Z28 Grille w/aftmkt fog lamps, MacEwen white-face guages
Electronics:
Alpine 8030 Alarm System, Valentine One Radar Detector (How did I ever drive without one?), Pioneer DEH 7450 Head Unit w/6-pack CD changer, Pioneer DEQ 7600 Sound Processor, 2 Kenwood KAC-846 Amps powering 2 12" Pro Red subs, 2 Pioneer 6x9 and 2 MTX 4x6 speakers.
NEXT UP: TBI mods, 3.42 gears w/Torsen posi

 

Where exactly is the coolant temp sensor?

 

Check for the existance of your air dam. (Read: Curb Scraper.) It's a flat black piece of plastic sticking straight down from your radiator that scoops up air as you're driving. If that's not there, no air is going to move over the radiator to cool it, and you'll obviously have overheating problems. It's about 20 bucks from a GM dealer, and only held on by several bolts.

The fan shouldn't come on until about 224-230 degrees.

Just because the water pump doesn't LOOK old doesn't mean it's not failing. But this isn't to say you should just jump to buying a new water pump. There's a few holes on the water pump that are meant to vent heat out, if coolant's leaking out of it, chances are the bearings are shot and the water pump is on it's way out. If you do decide to replace the waterpump, get a Stewart's.

There's several sensors that deal with the temperature of the coolant. There's one in the passenger side head, drivers side head, and one on the intake manifold. One controls the fan, one controls the temperature gauge, and one sends the temperature to the ECM for fuel metering purposes and what-not. I think the driver's side head is the temperature gauge sender, but I can't remember exactly what the other two are. The sensor that's in the radiator itself is the low coolant level sensor, I believe. I don't think that controls anything but the dummy light. Replacing the sensors couldn't hurt, just remember to drain some coolant out first, or it'll be running all over the ground. (A general no-no.)

If, when you turn the fan on by turning the AC on, your car cools down just fine, chances are it's just the air dam, since your car wouldn't appear to be having problems rejecting heat. Just in case, though, here are some other things to consider:

Look at the lower radiator hose and rev up the engine. If it collapses, replace it. It'd be restricting coolant flow.

Look at the metal in the radiator. It's not hard to see if it's corroded to the point of not effectively cooling any more.

I know this is a hard thing to gauge, but if it's really bad you'll know. Look at the amount of coolant being dumped into the radiator by the pump.

The car should cool itself while driving without the help of any fans, so long as you're not in stop-and-go traffic. The air dam should provide enough air flow at crusing speeds (around 45mph and above) to cool off your engine. If your car's temperature rises while you're traveling down the highway, I'm definately giving my vote for the air dam.



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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else

 

I have the black airdam though... That was the first thing I checked... Its there...Is it supposed to be angled at all?

 

The air dam should be vertical with the ground and is also a good thing to check.

The coolant temp sensor is mounted on the top front of the intake manifold (next to the upper radiator hose where your thermostat is). It has two wires connecting to it.

Like I said earlier, the ECM reads this sensor and turns on your fan when it reads hot. If your fan does not turn on this way, then this may be your problem

 

I had the same problem till I replaced the air dam. Make sure it doesn't give more than an inch or so at the bottom edge, or at high speed the air will fly right by it.