Status: Operational

[RAF7789]

after a whole month, 2 distributors, and possibly the better half of 100 hours of labor, my car is running once again. but there is still one problem ( ) , the temperature guage goes haywire once in a while when driving and it doesn't move past 160 degrees. could it need a new temp sensor? (i already made sure it was plugged in correctly.)

[97formws6]

Try taking the sensor out, hooking up a multi meter to the leads, and heating the sensor up with a heat gun (or hair dryer). The resistance should steadily change. If it stops suddenly, your sensor is bad, as a heat gun or hair dryer won't get as hot as your engine would. If it's not that, you probably need a new guage.

[ToplessFormula]

^ That's good advice exept the gauge doesn't measure air temperature. That's why gauges go to cold when the engine is overheated and the water is gone. Use hot/boiling water to check it.

[RAF7789]

I still haven't tested either temp sensor, but its on the list to do. I discovered that the skip shift comes on even if the temp gage in the dash is at full cold. So this means that the PCM still turns on the skip shift when the temp is appopriate. but i am wondering, if the temp sensor in the water pump is faulty, will the fans stay off? Is it possible for both the temp sensors (head sensor and wtr/pump sensor) to be faulty? I will be testing them both this week, but i just needed some knowledge for a peace of mind. Any help is appreciated, Thanks.,

_RYAN

[Injuneer]

Shoebox has a prodedure, including the resistance vs. temperature values for the sensors. It really doesn't matter whether you heat it with air or water.... the thermistor sensors all function the same way. Using a mixture of ice and water is a good way to generate a 32* test temperature, and boiling water will give you a 212* reference temperature, but that isn't the only way to do it.

The wire could be damaged, the pins could be damaged, sensor may not be grounded to the head properly (did you use anti-sieze or thread-locker to install it?).

Then you start talking about the coolant temp sensor in the water pump, and suggesting that may be faulty. What connection to the dash gauge are you thinking of? Are your fans not coming on, or on all the time? Yes, the PCM uses the reading from the water pump mounted sensor to control the fans, and anything else that is related to temperature.

Then you start talking about the skip shift light. What connection do you see to the temp sensors. I'm not aware of any.

[RAF7789]

The skip shift comes on when:

-you apply 35% throttle or less
-between 15 and 21 mph
and
-the temp is at 171* or higher how else would the PCM know the temp so it could turn the skip shift on?

Also, i haven't replaced either temp sensor, they are still the ones from the factory.

The gauge gets it's information from a sensor that is in the driver's side head. Inaccurate gauge readings can be from this sensor or it's wiring (the wire burned on a header pipe is common).

[RAF7789]

ok so i just went to go test my temperature sensor for the dash gage and i could not believe what i found. The harness was plugged in but the wire for the harness looked like it had broke off, and the previous owner just taped it back together. so now i will buy a new harness +wire. I think i have found my problem.

[97formws6]

I had the temp sensor go out a while ago. I found out that it was cheaper for me to buy a full autolite temp guage kit than to buy the factory one. I just stuck it in the middle air vent. Just a little FYI in case you might want to do the same thing.