Temp gauge and MPG Gauge not working??

[ME30W]

The temp gauge is sitting very low into the blue, even through my 1 hour commute on the highway. When I did hit traffic it climbed up a bit, but went right back down when I started cruising at 70mph again.

Also, the MPG gauge is stuck at 40+ mpg, even when I turn the car off.


Not sure if both problems are related, but they seem to have happened at the same time. Am I going to damage the engine if the temp gauge is sitting so low?

[jlevie]

If the gauge is a true reflection of the engine temperature, the thermostat has failed open. and the engine running cold. That will increase fuel consumption, tend to cause carbon deposits in the head, and can lead to catalytic converter failure.

But is is possible that the SI board is bad or that the gauge isn't making a good contact with the PCB in the cluster. A bad SI board could also cause the econometer problem. A check of head temperature with an IR or contact thermometer will tell where to look for the temperature problem.

[ME30W]

I'm scheduled to get my timing belt/water pump/thermostat replaced this weekend, so it sounds like good timing.

Just wanted to make sure I'm not causing any damage to the motor while I have to drive on it this week.

Thanks for the help.