pzzo757203

ok i drive a saturn sl2 97 the problem im having is tht when im at idle r even parked with my car running my rpm will shift by it self from 1 to 3 and i can put it in park and get out of my car and it will still be at 3000 rpms

also my temp on my dash moves around but it doesnt ova heat and it will also shut off on me and then it takes a min to get it started again

thax in advance

L_U_C_K

To preven it from over heating you must BIWP.

Dough_Boy.

It's either the temp switch for the computer, or the computer itself. But if you are going to try a temp switch make sure you tell them it's the one for the computer.

pzzo757203

its the needle in my dashboard tht moves around it doesn't over heat but the main problem is when im in first gear it will jump up to 3000 rpms by it self r jump down to 0 and cut off its a automatic

Laserjock

there's your problem right there.

Search clean IACV if Saturns have it.

pzzo757203

yea i have one i a try tht

Dough_Boy.

I understand the idle is jumping around. The temp switch for the computer helps control the idle. When that starts to go bad that's what they do. Then when they go completely bad the car won't start.

Fabrik8

Most cars have a separate coolant temp sensor for the ECU and for the temp gauge. So if the sending unit for the temp gauge is going bad, that won't affect the ECU at all. It's possible that there is a bubble in the coolant system, which could affect both of them if the sensors are in roughly the same region. The needle jumping around a lot is a little strange.

the idle problem is more likely a clogged IACV or something similar.

Dough_Boy.

It's the temp sensor for the ecu. We see them all the time at the shop. It's most common in cavaliers and saturns, with the 2.2. I don't even think they have iacv that's what the temp switch for the ecu is. Then it will also make the gauge jump.

TATTRAT

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