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My temp gauge has progressive started to spike more and more. Jumps from a normal reading to 250 or 260 nonstop while the car is running also when the car is off and key is turned forward. Gives "Coolant over temp" warning seemingly 5-6 times a minute. These readings are not accurate to the actual temps. I have changed the coolant temp sensor, and looked for burnt/torn wires with no success. Only codes showing are for the o2 sensors due to the headers, and c1286 steering sensor bias malfunction. is a 97 with ts headers/xpipe.
I've seen the temp gauge on our racer do that when we had a coolant leak and we were way down on coolant. The senders can't read air so when the coolant was below the sender the gauge dropped then boiling hot coolant would hit the sender and the gauge would spike. Does it do it when you first turn it on in the morning? Does it need to be warmed up first or does it do that immediately upon starting it?
I've seen the temp gauge on our racer do that when we had a coolant leak and we were way down on coolant. The senders can't read air so when the coolant was below the sender the gauge dropped then boiling hot coolant would hit the sender and the gauge would spike. Does it do it when you first turn it on in the morning? Does it need to be warmed up first or does it do that immediately upon starting it?
I seem to have enough coolant, reservoir has the right amount and I haven't found or seen any leaks. It usually takes ten or so minutes from cold start to start showing the problem
Other threads seemed to imply the fluctuations wouldn't be so frequent or quick to change temperature. How could I check to make sure this isn't the problem anyway?
Done any coolant changes just before this started? Added, changed fluids?
Burp the system.
Unsure if air will cause your problems, just throwing an idea out.
This problem did eventually return. It was the wiring for the coolant temp sensor. It does not show any visible wear but I was able to make the problem go away by routing the wiring away from headers.
Last edited by Logan Youngblood; May 18, 2019 at 01:07 AM.
MY 01 z06 temp gauge was having erratic movement 0 to red line and back, replaced the sensor. Still had problem, moved the wire to the sensor away from behind the alternator and problem fixed. The wire was likely grounding out.
I would start by replacing the coolant temp sensor on the drivers side of the block next to the alternator. Also, replace the coolant and make sure you follow the prop burping protocol.