My 2001 Malibu with 3.1 temp guage is not working. I have replaced the sender twice, but it only works for a few weeks before it quits. Any ideas as to why it would do that?

 

When you say "it quits," does it register cold or hot? If cold (or ridiculously cold in a scanner readout), you probably have a break in the wiring which the PCM senses as maximum voltage drop across the ECTS which translates to minimum temperature. Since it does work some, there probably is an intermittent connection inside or near the electrical connector. With the key ON engine OFF, one of the pins on the connector should have 5V and the other should be at ground potential. Pull the connector off the ECTS and then check the signal levels while flexing and/or pulling the wires at the connector.

 

Makes sense. I've thought about that, but wasn't sure how to test it.

Thanks.