Thermostat

Chris2000 · 01-19-2010, 10:59 AM

Alright so for about a week now the temp gauge after about 10 miles of driving fluctuates between half and the next line above, its not like it goes up there slowly to tell me its actually overheating, but its more of a rapid jumping up and down and then stays up there and then comes back down about a minute after. Is this something major or maybe just since the car hasn't seen snow in 5 years it's just not used to it and just gotta change the thermostat?

Also, when i park the car in the garage i sometimes hear a little squeaking so i popped the hood to take a look and it seems that one of the belts is squeaking. None of them have been replaced before, so maybe its just time for some regular maintenance?

jayson_waltz · 01-19-2010, 11:21 AM

squeaking is likely just a stretched belt. replace it.

the temp needle jumping like that but quikly back and forth like you said is not the thermostat. the thermostat doesn't actually tell the temp of the coolant or send any signal actually. it just opens when the coolant gets to a certain temp, and closes when it cools off. its spring controlled somehow, not electrical.

It sounds to me like you have a temp sensor going out. its a separate part. i don't know exactly where it is, but chime in what motor you have and someone will tell you

Chris2000 · 01-19-2010, 11:23 AM

It's the 2.4. Thanks though.

[ion] C2 · 01-19-2010, 11:41 AM

Quote:

Originally Posted by jayson_waltz

the temp needle jumping like that but quikly back and forth like you said is not the thermostat. the thermostat doesn't actually tell the temp of the coolant or send any signal actually. it just opens when the coolant gets to a certain temp, and closes when it cools off. its spring controlled somehow, not electrical.

So why can't the thermostat be sticking and not letting the car get cooled down?

How quickly are these "jumps"? Like is it jerky or smooth? Could be the ECT sensor, might try that first.

Gr1m · 01-19-2010, 11:49 AM

i would spray your belt with some brake cleaner, that should get whatever it is off of the belt, and if that doesnt work i would replace it with a gator belt

Chris2000 · 01-19-2010, 08:57 PM

Quote:

Originally Posted by [ion] C2

So why can't the thermostat be sticking and not letting the car get cooled down?

How quickly are these "jumps"? Like is it jerky or smooth? Could be the ECT sensor, might try that first.

Its jerky. like all the way to the 3/4 mark then all the way back down to 1/2 then all the way back to 3/4 for a minute then back to 1/2

[ion] C2 · 01-19-2010, 09:24 PM

I meant like instant jumps of the needle, very, very fast. Not smoothly going from 1/2 to 3/4 or whatever.

Most likely thermostat.

Chris2000 · 01-20-2010, 01:42 PM

Quote:

Originally Posted by [ion] C2

I meant like instant jumps of the needle, very, very fast. Not smoothly going from 1/2 to 3/4 or whatever.

Most likely thermostat.

Weird thing happened today. It didn't jump at all so far. Perhaps after hitting a big bump or pothole or something the thermostat jumped out of place and was loose and wobbling around fluxuating the temperature? Now it is staying on the 1/2th mark but i'll let you know if anything changes.

Chris2000 · 02-24-2010, 01:33 PM

So I think I figured out the problem that relates to this.

The SES light came on so we pulled the code and its for bank 1 sensor 1 heat circuit malfunction (oxygen sensor before the cat) so we were going to replace it but we had the wrong one.

Symptoms of the car:
1) first time in the morning i start the car the rpm's start at about 1750 and keep going up until about 2k-2250. After the car heats up a little it drops down
2) while this is going on there is a lot of white smoke coming out of the exhaust

So i'm guessing that because the sensor is bad it isn't telling the valve when to open/close which is causing the high rpms and lots of smoke because it has no clue if the car is cold or warm at first.

So if anyone has experienced something like this let me know if replacing the sensor is the correct way to go. Again it is the 2.4 Alero 2000 4 door. We are going to replace the short wire sensor (sensor 1 closest to the engine) because thats what the code said.

Also today was a pretty rough day, on the way to school i got rear ended. It wasn't bad except for the part that my car had to touch a chrystler sebring

. His front license plate bolts pushed into my bumper so i got two wonderful little holes from that. My back is hurting pretty bad so i'm going to get that checked out either today or tomorrow. On top of that, the cops around here are doing an emergency snow plan all day so there was nothing i could do today for reporting the accident. Got all his information and stuff and the kid was afraid of me when i got out of the car he was pretty much kissing my feet admitting it was his fault (thank god we won't have to go through an annoying debate about if i brake checked him or if it was his fault; which i did not brake check him i was completely stopped he just slid in to me as he said).

[ion] C2 · 02-24-2010, 03:04 PM

There's no heater circuit on the upstream O2 from the factory. lol

The oxygen sensor doesn't tell any "valve" to open/close. If you're talking about the ECT (engine coolant temperature) sensor, and it is bad, that could cause the issue you're describing. Just change it, it's like $15.

If that's not it, your high RPM situation sounds like a problem with the Idle Air Control Valve (IACV) or a large vacuum leak.

Nate's Alero · 02-24-2010, 03:58 PM

white smoke, was it like, frilly and evaporated quickly? or was it heavy and stayed around for a long time, and hung close to the ground..., change the ECTS, and get back to us

Chris2000 · 02-24-2010, 04:19 PM

Quote:

Originally Posted by [ion] C2

There's no heater circuit on the upstream O2 from the factory. lol

The oxygen sensor doesn't tell any "valve" to open/close. If you're talking about the ECT (engine coolant temperature) sensor, and it is bad, that could cause the issue you're describing. Just change it, it's like $15.

If that's not it, your high RPM situation sounds like a problem with the Idle Air Control Valve (IACV) or a large vacuum leak.

we pulled the code and it said heat circuit malfunction bank one sensor one so what would that be?

Quote:

Originally Posted by Nate's Alero

white smoke, was it like, frilly and evaporated quickly? or was it heavy and stayed around for a long time, and hung close to the ground..., change the ECTS, and get back to us

evaporated quickly went into the air.

[ion] C2 · 02-24-2010, 05:01 PM

Well there isn't a heater circuit for Bank 1 Sensor 1 so... what was the code number?

Change the ECT...

Chris2000 · 02-24-2010, 06:06 PM

Quote:

Originally Posted by [ion] C2

Well there isn't a heater circuit for Bank 1 Sensor 1 so... what was the code number?

Change the ECT...

No clue what the code # was, dad wiped it without letting me actually look over it.

I'll try changing the ECT I guess.