Been living with my temp gauge reading high since I got the truck, and now since I put in an upgraded 140amp alternator, am dealing with a pressure gauge problem as well.

Whenever my RPMs increase, it seems my pressure gauge will drop like a rock. My temp gauge seems to drop a tad as well at the same time. Once I get off and start to get back to an idle, the pressure gauge will even out to where it should be.
Anybody know why installing a new stronger alternator might cause this problem?
I'm going to buy some after-market gauges to hook up for pressure and temp, anybody have any tips on this? The pressure sending unit thing looks like its gonna be a pain to get to... not really looking forward to this fix

 

The oil pressure sender is probably bad. Does it have oil dripping out of it? They're only ~$15 @ NAPA.


Ignore the gasket.

There are several threads on FSB about adding aftermarket gauges to pre-'97 trucks, so do some searching over there.