I have a 97 gt with the 2.4 and a 5 speed. Recently it's been running hot while stopped in traffic, so I changed the thermostat (195 degree) flushed it out and put in fresh dexcool. I believe it's a bad thermostat because it's still heating up almost to the red when stopped or at a drive-thru. On the freeway I can drop the guage to "below halfway" by driving in 4th instead of 5th gear.
So my question is... I'd like to know what is the lowest degree thermostat available for this engine? I'd also like to put in a lower degree fan switch to match a lower thermostat while the system is drained. Anyone have part numbers or a website I could go to?
Also, the fan seems to have a mind of it's own. It turns on and off while the engine is cold and the ac is off. The fan stays on once the guage gets high or the ac is on. What would cause this?
Thanks!
John Wilken
2002 Cavalier
2.2 Vin code 4
Auto
This is a myth.
Installing a colder thermostat will NOT make the car run cooler. It will still operate at the same temp as before, just that the engine operating will be coller in colder weather. Also installing a higher temp to make it heat up faster is a myth. It will still heat up at the same rate, just will operate at a higher temp.
It sounds like your fan is not coming on. The reason I say this is because the car iverhetas in city driving only, well that is the only time the fan is commanded on. The fan does not come on, on the highway. There is enough airflow at that speed to make the wind turn the fan, and combined with the airflow across the radiator.
I would first check does the fan spin freely by hand.
If yes, I would look at is it ever coming on. A faulty ECT sensor will cause the fan not to come on.
If the ECT is good, then look at fan itself. Does it have power to it, ground, is the motor shot?
good luck
- 2004 Cavalier - 124k, owned since new
Plugged radiator. I had the same issues with my 95 GAM 2.3 Q4
When you say flushed, did you use a flushing addative?
C.T.S wrote:Plugged radiator. I had the same issues with my 95 GAM 2.3 Q4
When you say flushed, did you use a flushing addative?
I didn't use any flushing chemicals, just lots of water. I've used chem flushes before and ended up with heater core/rad leaks, so I stick to plain garden hose water for flushing now. The rad may be plugged, but I'd like to start with a colder thermostat and fan switch. I've never used any rad sealer in it... Maybe I'll pull it out and get it flow tested while the system is drained.
RobS, thanks for your input, but I have to disagree with you about a lower temp thermostat. In my first car, a 71 Grand Prix, I put in a 180 degree thermostat and once warmed up, the car stayed at 180 degrees. Over a winter I added a cam, ported/polished the heads, new pistons, eldebrock intake, holley 750cfm carb and hooker headers. To get the most out of it, I went up to a 195 degree thermostat, and the car stayed at 195 once it heated up. But that was in the old days when cars only had a distributor and a carb instead of 10 miles of wire and electronics.
My cooling fan does spin with the a/c on, so I assume the fan motor and relay are OK. I'm looking for part numbers for a lower degree thermostat and matching lower degree cooling fan sensor. Where's that MrGoodwrench guy? He usually has part numbers for everything...
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John Wilken
2002 Cavalier
2.2 Vin code 4
Auto
if it was a plugged rad, it wouldnt cool down at highway speed cause the air moving through the rad wouldnt be used. it is mos certainly a fan issue. oh and bout the ECT sensor, it's not gonna be that either if his gauge is working. check you fan fuse and relay, if they check out, check wires, and iif they are fine, suspect a fan motor.
sunfirepower97 wrote:if it was a plugged rad, it wouldnt cool down at highway speed cause the air moving through the rad wouldnt be used. it is mos certainly a fan issue. oh and bout the ECT sensor, it's not gonna be that either if his gauge is working. check you fan fuse and relay, if they check out, check wires, and iif they are fine, suspect a fan motor.
Okay since your clueless here.
The car has TWO sensors one for the gauges, and one as input to the PCM. the ECT is the input to the PCM, yes it can can be that.
- 2004 Cavalier - 124k, owned since new
Rob S wrote:The car has TWO sensors one for the gauges, and one as input to the PCM. the ECT is the input to the PCM, yes it can can be that.
I was only aware of one sensor for coolant, where are these two and which one is for which?
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John Wilken
2002 Cavalier
2.2 Vin code 4
Auto
actually i can still prove you wrong on that, there is ONE SENSOR, and ONE SENDER. if the sender is bad the gauge would read wrong, if the sensor is bad guge would be unaffected. but upon going through my schimatics, these dont have a seperate sendr and sensor, meaning the sensor provides the data for both PCM and gauge.
the sensor is in the head, on the right side (facing the front of the car) near the water outlet
sorry, scratch that last one, its on the thermostat housing, in back of the engine
I replaced the ect on the drivers side at the inlet to the engine. What's the piece on the thermostat housing called so I can ask for the right part?
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John Wilken
2002 Cavalier
2.2 Vin code 4
Auto
