I connected my oil pressure gauge to the factory sender, but when I turn the key to "on" the gauge pegs at its max and stays there even when the car is running. It is the same when the sender is unplugged. When I turn the key back off, the gauge slowly returns to 0.

Any clues ? ? ? What am I missing? It water temp works fine and the other gauges seem to as well.

Thanks,

Don

 

Sounds like you have a constant ground problem. The gauge is grounding out and your getting a full needle deflection. I would remove the gauge from the dash and see if you can get it to work unmounted. I only has to touch on piece of metal in the dash to cause problems. Good Luck!

 

oops..

 

As a guess (I can't really remember) but the cause of the problem is somewhere along that tan line, it has a broken connection. My camaro has an idiot light sensor still screwed in (wasn't worth the hassle geting to just for oil pressure) but, weather the wire is on or not, the oil gauge stayed pegged over 60 as soon as the key is in the 'run' position (idiot light sender normally open/no ground)

You may have to do some hunting under the dash or, pop out the cluster & run your own wire from the backside of the bulkhead direct to the gauge (personally I'd say the 2nd would be easier).

If you were to ground the wire the gauge should read 0 which would confirm is the wire has a break in it somewhere. Keep in mind, wires can break internally once in awhile so you may want to try a jumper from the bulkhead to a ground to see if that get's a reaction, if not it's something inside the car.

If there's an excessive amount of teflon tape on the threads, sometimes that can keep a sender from properly grounding.

here's a (very crappy) pic of what the press unit looks like, I'm sure you know you've got the right one but just for comparisions sake...

 

That's kinda' what I figured it must be. It behaves like there is an open connection somewhere.

That's pretty much what I am planing on doing.

Thanks for backing up my assumptions! It makes me more confident that I'm on the road to solving the dilema.

Don

 

Before you rip it all apart, you could simply re-wire it. Cut the old wire, usually brown (??) coming off the sender, you know the one, and just hook it to a new guage and run your own wire. it may look sloppy, having a separate sensor, but if your like me you plan on removing your factory guages anyways, even if its one at a time.