I have 94 Mazda Protege, has 108000 miles.
Last friday suddenly the temperature needle started to move towards HOT pretty fast. I had to stop and had it towed to the mechanic.

The mechanic after doing many checks is still not 100% clear on what could be the problem. He changed the thermostat, some swicth, ensured that engine temp. per-se is pretty normal. Appears there is no co-relation between the Engine Temp and Temp. gauge readings. He looked into coolant seems to be fine., there is no leakage anywhere.

One of the very important thing noticed was within less than 30-40 seconds the Temp. Needle shoots to liitle bit more than 50% from overnight idle condition. While driving it keeps moving very slowly towards Hotter side. Many times alomost it is close to Hot side (95%).
The mechanic is now thinking that it could be resistor under the dash board could be sending an incorrect information to the Temp. Gauge. He plans to change the whole Dash board. He feels 99% certain about it.

Any ideas ? Any help is appreciated..

Thanks

 

I have the same problem, though a new gauge cluster probably won't make difference (I did that allready for the tach). It looks like something wrong with the wiring harness, or the sensor/engine block connection is corroded, which is crucial because it is a one lead sensor for the dash temp gauge. Even the use of antisieze can cause the temperature gauge to act all funny because of the change in resistance in the circuit. In theory there are only 4 reasons why the temp would go up that high, #1 car is overheating, #2 sensor is dying/has a bad connection to the block, #3 bad harness, and #4 bad dash cluster. I hope this helps

 

Thank you very much. I will have mechanic look into the suggestions you posted and I will post the feedback.

Thanks
Brao

 

i had the same problem if anything its like the other guy said its your gauges i had the same problem its no thing i looked back to past recalls and that was on the top of the list those gauges are notorious for doing wacky ****,just like the seat belt warning light on the cluster, my gas gauge has just started giving me problems to.That is **** that you just got to deal with.

 

This is the same kind of thing my 91 DX is doing. Quickly shots up to about 50% then slowly starts rising to the H side. I have checked for radiator leaks and there are none, fans all work, no boil out, just a jacked up temp guage. Found something weird though... if I drive in 3 gear between 40 - 45 mph the guage will actually drop, even though the rpms are going higher thus causing more heat, the guage drops. Strange things are a foot at the circle K.

 

I have a 95 Portege and the temperature gauge does not work at all. I think that the sensor is bad but I am unable to figure out where it is located. I will appreciate if some one can tell me where to find temperature gauge sensor on the engine.

Thanks

 

Dos it shoot up while at a stop or when driving.
If it happens while sitting, then its probably fan not working.