The factory gauge in my 1991 Volvo 240DL is on the fritz, sometimes it work, sometimes it does not.</P>


This is my "beater" car, I only drive it around town instead of driving my other cars. I basically go back and forth to work in it.</P>


I have picked up an aftermarket temp. gauge and I have it all wired up and I am just wondering if anyone has installed one on this model. On other cars, we usually tap the waterneck above the thermostat or get it off a cyl. head or intake manifold.</P>


I know I should just fix the problem with the factory gauge, but I would rather have a gauge with numbers also. OnceI know it is not getting too hot I can go to fixing the factory gauges.</P>


I have noticed that there is no coolant leaks, no level change in the overflow tank, radiator is staying full also.</P>


More than likely, there is nothing wrong with the temp. but I want numbers to prove it.</P>

There are four things that can go wrong with temp guage in a 240. Bad thermostat, faulty sending unit, faulty guage, or faulty temperature compensation board. Sounds like your thermostat is ok. I'd replace the sending unit for good luck. It's cheap. If your guage is still moving around then it is probably fine. Then the cuplrit is the TCB. This is a circuitry board in the back of the instrument panel, which you must remove and replace. They cost about $90 from Volvo but it will fix your problem.