Fuel Guage and Temp Guage Problems

["Tim Tomlinson" <tomlin@xxxx>]

Hello, all,
1. I've been reviewing the recent spate of e-mail with guage problems with much amusement. I hope someone comes up with some good ideas as one of my 300-K's has the same problem(s).
2. One of my problems, the always full or nearly full fuel guage, seems to be fixed. Will have to wait a while to be sure. It was fixed when it was discovered that a dash light tail for the cruise control (which it doesn't have) had been connected to a terminal on the rear window defogger that fed back to the dashlights and possibly the guage when the car was turned on. I, too, had done all the checks with everything checking OK. Been that way since I bought the car in 1990, and just now was found.
3. The temp guage also checks out OK. Did the grounding at the sender unit, multimeter the voltage going to the sender, replaced the sender (several times, they're cheap), etc to no avail. It will read midguage under local driving when it is hot weather, but have symptoms of overheating long before the guage shows it. On the road it barely wiggles up to the beginnings of the guage mark. My other 300-K (the one I think of as the evil son) works just fine and accurate to the fuel and temp guages. 
4. I wonder whether the guage and or sending unit have been replaced and not matched to each other? 
5. Thoughts and SOLUTIONS would be much appreciated--it gets frustrating after 13 years of trying to fix it.
Tim
2-300-K's


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