I was out for a fun, spirited drive yesterday and I was cruising along a lonely old road at 85-90 mph. I drove like this along this road for about 40 miles, then I had to make a 'pit stop' to take a leak. I got back in the car then made a cell phone call, and while I was talking I noticed my temp gauge was reading quite high, nearly to the top of the normal range. I've never seen it go quite that high before. I sat there for a minute with the heat on full and revved the engine to 1500 rpm to see if it would cool down. It dropped slightly but it was still high. It didn't drop down to it's normal position until I started driving again. I don't think my radiator fan came on at all, at least I couldn't hear it. Normally, for whatever reason, my fan is on all the time but lately I haven't heard it running. What should I check?
There should be a fuse you can check for it, and you can also use jumper wires off of your battery to test that the fan is working properly.
Rob
Sold 2/2/05
I pulled the fan fuse and it was ok. I then swapped fan relay's with my brother's 95 Cavalier parts car (ooh it's good to have a parts car) and it worked, the fan is back on. All the time, actually. I'd rather have the fan on all the time, that way at least I'd know it's working, than to not have it come on at all. I suppose I should check into why it is on all the time though.
You made that cell phone call, that made it over heat
J/k!
Don't freak out if the temp goes over 195F (1/2 way)
if it goes over 240F, then start to worry, but if it goes back down to at least 210F with the fan on, don't worry.
240F is to hot, infact I doubt with aluminum heads it wouldnt take 220 to well either.
Also the fan on all the time is not good either.
If the fan is on all the time, it can be a caused be a shorted relay interlaly, or the ECT sensor is faulty
- 2004 Cavalier - 124k, owned since new
How do I tell what's 195 or 240? Stupid temp gauge in the Sunfire doesn't have any number markings. If the ECT was dead would that set a CEL? I notice my check engine light sometimes goes out, then comes back on for no detecable reason, but now I'm thinking maybe the ECT has a broken wire or something. I remember when I bought the car, the owner told me he had the motor changed so maybe it didn't get put back together right? Everything else seems to work fine on it though.
The fan comes on at 230F-235F degrees automatically.
and I agree. That is too hot, but that's the GM way.
I thought the same "OH MY GOD!! MY CAR IS OVERHEATING!!!"
that's why the head warps. I think the fan should come on at 200F
I drove a mercury Sable and the temperature stayed the same at all times
on the highway or during traffic.
The cavalier's temperature goes up and down like a roller coaster.
as long as you don't use words like "Leak" or "temp going to the red" or
"Overheating during traffic" "leaking" you might be okay.
Yeah, I know what you mean about the temps going up and down all the time. It worried me a bit when I first got the Sunfire it bothered me, especially when I was idling in traffic. I learned it's normal and now it doesn't bother me.
Its normal for any car for the temp to go and down. Think about it, your driving at 70, get off the highway idle for a inute, go up to 40 on a city street, then down to 25, then idle here and there. It doesnt take a heart doctor to figure out the temp will change a lot to.
No the fan does NOT come at 230, one person said that and now everyone does despite the many times I have said they are wrong. I dont know the exact temp but somewhere around 195-210F it comes on.
195F is normal temp for the car to run
If an ECT is not working, you may or may not get a CEL, depends how it fails. If a wire was damaged, ground or signal than yeah it would give a CEL, however if the sensor failed and reads 3.2V all the time the computer may or not see a fault with it.
It could be an intermittant fault as well.
- 2004 Cavalier - 124k, owned since new
Ok, I did some Googling to find a suitable picture of a early Sunfire dash so I could mark it approximately where my temp gauge needle was. I found one on eBay, the white mark is right about where my temp gauge was at, maybe a bit lower than that. You might have to download the pic then zoom in on it to see it better.
Where that white mark is (not the needle) looks to be within the safe operational range of 195-200, but like everyone else says if it's in the red trouble may happen.
that's SAFE
if you really want to know the temperature of your car when it gets that high, connect a scanner and read the current temperature.
that's about 210F, I would say.
My fan comes on when the temperature goes over 230F
I'm almost 100% sure that's why my cylinder head warped.
After 180,000 miles
Bottom line is, the temp should stay at 195F at all times, during traffic or on the high way.
The cooling fan is capable of reducing the temperature down to 150F and that's why we have a thermostat to keep the temperature higher than 195F and
The fan should come on more constantly during traffic
