[KeithO]

My fuel gauge has always been wrong on my 1995 Firebird. When the gauge comes off full, I know that I need to get gas fairly soon for street driving and immediately for track driving.

Yesterday through the use of a scan tool, I also learned that my water temperature reads way too low while also learning that GM has two water temperature senors in the car - one for the ECM and one for the fool behind the wheel. The ECM sensor seems correct and the in-dash water temperature gauge is wrong.

Should I be treating these two problems as separate or is it possible that these are related?

[Jon A]

It's possible when you observed that difference, the water coming from the radiator hadn't been through the engine yet. It will vary depending upon a lot of variables.

I've found when it's settled into a nice steady state, lightly cruising so the engine isn't producing much power at all, the gauge only reads a couple of degrees below the PCM. When you put your foot into it very long, the difference gets much bigger.

I was actually planning to move my sensor for the gauge to the same spot as the PCM a while back as I think the coolant temp after the engine is the more important one to monitor. I just never got around to it. I'm glad you reminded me. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/wink.gif)

Don't get me wrong, your gauge certainly may be off. I'm just trying to point out it really is reading a different temperature, so it might not be. You could always swap the sensor location and see how it works. An aftermarket gauge would be nice, but if you're on a budget it's nice to know something really is broken before you replace it.

Let me do some searching of my notes...there's a Corvette sensor that fits where the PCM sensor is except it has a wire for the PCM and one for the gauge. I forgot all about that mod, I guess I got too busy last year. I just kept in the back of my mind that whatever the gauge said on the track was probably 10-20 degrees or so lower than reality.