I've notice lately my Gauge Mark oil pressure gauge doesn't return to zero with key off. Seems to work OK otherwise, hot 40 to 60lbs oil pressure. I just thought I remember it returning to zero when I turned off the car. Any ideas? TIA.
I believe I just never noticed this. Gauge sits at whatever the oil pressure was when car was shut off. Turn car back on and gauge returns to zero until engine starts and sender sees oil pressure. I believe normal operation, I just never took notice of it.
I had a TA that used to do this. It was oil press, temp and tach that would stick and my OCD wouldn’t let me leave it like that. So I always had to cycle the key after shutting the car off so the gauges would “zero out”
Sorry for the late reply, but you're correct! The gauge will return to zero with switch on. Otherwise, it remains fairly constant with the pressure it was showing at key off. These gauges are (were) built from original GM components which did not have a return to zero function. Lately, I am using modern electronics that do return to zero. Functionally, they have the same accuracy.