American Motors: Gas & Temp Gauge Readings Jump Around..., kennedy amc, amc javelin

Question
Hello,

I have a question about Dash gauges.
The car is a 74 AMC Javelin.
The Gas and Temp gauges seem to work OK when the car is first turned on but after letting everything warm up and driving around for about 15 or more minutes the needles on both the gas and temp gauges start to jump up and down slowly.
And as time goes on the readings get lower and lower till the temp gauge is almost all the way down and nearly all the way gown for the gas. Again the car is compleletly warmed up and the gas tank is about 3/4 full. Running the lites, heater etc, does not seem to cause the condition to change.
I read that there is a voltage regulator on the back of the Dash cluster, would these conditions point to that or is there something else I should look at.
Additional note: Once when the temp gauge was all the way down I touched the sense lead to ground but the gauge did not move.? I'll try it again when cold and see what happens.

Thanks For Your Time.
Dave Buck


Answer
It does sound as though the CVR (constant voltage regulator) is the cause of your problem. It is located on the back of the instrument cluster and either plugs in or is held on by 2 small nuts. Contact an AMC parts vendor for one. Try American Performance in Coaca FL or Kennedy AMC in Ohio. Good luck.