sea-level

Car off or on, the temp guage is at 180 and never moves. Any ideas? It just strated doing this out of the blue. Car is running fine and doesnt appear to be over heating or anything like that.

Thanks.

Joshiedoom

iTrader: (4)

Unplug the ECT sensor on the drivers side of the block up front next to the manifolds.

See if it changes, if so, then its dead. if not it could be the guage

youngrigo

What year is your car? Cuz if its a 99-02 fbody they are dummy gauges anyways and good for nothing

Jon@Texas-Speed

iTrader: (18)

Probably just need a new coolant sensor. Replace it and that should fix the problem.

Jon

CayenneRedV6

iTrader: (8)

I've never understood this. I find it hard to believe that GM would put a coolant temp gauge in a car that doesn't work. I could see it being inaccurate and the temps it shows not being quite right, but being a "dummy" gauge that's there just for looks just seems like BS to me.

youngrigo

Well if you ever ride in one of these cars you will see that the needle never moves (Unless your overheating) so it basicly stays at 210.

I have a auto meter one hooked up in my car and i can tell you that my cars temp jumps from 160 if driving in the freeway to 210 if stuck in traffic. The stock gauge does not move if your car is anywhere from 160 to 230 i beleive it is. It only moves up higher from that once your car reaches over 230 and by then your pretty much getting ready to overheat these aluminam blocks.

sea-level

Mine is a 98 and it has fluctuated accordingly so far until today. I'm about to play with it and see what it says.

SOMbitch

iTrader: (8)

Make sure you get a 98 specific CTS. It is a different part # than the 99-02 that are the dummy guages. I had to get mine from a dealer.

sea-level

Ok, so I unplugged the sensor and the guage dropped to nothing pretty much, no response at all. I noticed that it actually moves but it never goes past 185. It used to fluctuate and all of sudden it is not. It would go to 210ish, the fans would kick on and the guage would trickle back down. Is there a secondary safety I can rely on if the car starts to overheat? If that sensor or guage is bad is there something in place to keep from spontaneously combusting into flames? It's not my daily driver but I'm not ready to do a rebuild just yet. Im trying to get axle bearings and little things like that in order before I start tearing into the motor. And ****...

sea-level

Im going to replace the sensor just to be on the safe side.

Weezzer

Let me try to explain. In the 98 year the temp gauge read correctly. In fact it worked so well with the aluminum block that the gauge reading would fluctuate over a vast range as the block would heat up and then cool down as the thermostat opened. Many customers would seek "warranty" work to solve this temperature fluctuation problem which in actuality was non-existent (it was performing exactly as designed). In the '99 to 2002 year the gauge was configured to be a "dummy" or "idiot" sender. It reads a constant 210 degrees for the actual temp range of 180 to 226 degrees. Above 226 and it will then revert/show the actual temp.
The computer does see the "real" temp, but the gauge is hooked to the computer via a serial port connection (as I understand it). The computer interprets the actual signal, then sends the dummy temp reading to the instrument cluster. Either live with it or put in a custom temperature gauge - like most folks do...
Those are pretty much your altenatives without spending big bucks....

Joshiedoom

iTrader: (4)

My temperatures never goes above 185 when cruising at all. I have a mid 98. It only goes higher if im setting for example in the staging lanes, but thats what fan switches are for. The 1998 ls1 owners manual says this is normal. I can take pics of it if you like. Change the ECT and if you still have trouble get a new thermostat. It might be stuck wide open... same issue I had.... It would heat up but never get past operating temperature.