Hello out there. I just noticed that my VDO "graduated" temperature gauge (the aftermarket one with the temps on it (120 to 300F)) gives a reading that "jumps" up 20 degrees when I turn on either the parking lights or the head lights. I have tried wiggling wires and tightening the terminal on the sender. I know the sender's resistance goes down as it warms up, since grounding the wire out pegs the needle, so I am thinking that it must be some "partial short" involving the harness (tail lights?). Is there a place in the harness that is particularly vulnerable to this? Is there some other "weirdness" that occurs with these cars?
Car is a '73 2.0 four cylinder, pretty much stock.
Thanks for any guidance.
-Jim