oil pressure gauge not working

[kbw87]

I've got an 87' with an oil pressure gauge that is pegged all the way to the right.  Does anyone know if this is a sensor issue or gauge? 



Thanks

[4x4HighSierra]

Most likely the sending unit behind the distributor on the drivers side has gone bad.  Or it has come unplugged and is grounding itself out causing the gauge to peg itself.

[Irish_Alley]

does it do this with the key on or off? if it stays pegged out it would be the gauge if it does this when you turn the key on it should be the sending unit

[ohio hab]

I once  had this problem on my 84 C-10, and the problem was caused by dirt, sludge, in the sending unit.

[VileZambonie]

check the connection at the sending unit first.

[kbw87]

I was assuming the sending unit was the sensor that threads directly into the block.  I did pull this wire and check the connection to and no luck. 

The gauge stays pegged to the right key on/key off.

I haven't pulled the dash panel off yet to check anything with the gauge yet.  Maybe i'll pull the gauge then.

[VileZambonie]

Did you check the oil pressure switch or the oil pressure sending unit?

[Irish_Alley]

going with vile it almost sounds like you just said you tested the switch on the side of the block the sending unit is in the intake manifold behind the distributor

[78 Chevyrado]

I broke the connector on my sending unit while doing a tune up.  it stays pegged all the way to the right at about 2:00.  I'd get a new sender.

an 87 has 2 oil psi sensors.  It's the big soup can looking one by the oil filter is for the gauge.  On the older trucks the big can shaped one is up by the intake.

[kbw87]

Good pic - great info.

I didn't realize there was 2 sensors.  I had only been looking by the exhaust manifold.  My gauge is in that 2:00 position as well.  I will check the connection first thing tomorrow and start there.  

Thanks for the help guys.

[Layne]

Don't mean to butt in here, but which one would you hook up a mechanical guage to? IE Autometer?

[VileZambonie]

A mechanical gauge would require you to run a direct line from any oil gallery tap.

[Irish_Alley]

most time with mechanical gauge people just remove the sending unit but the distr. and replace it with the hose and fittings the gauge comes with

[Layne]

I TEE'd into the one on the citation. Figured I'd do that. but didn't know which one would be better or if I can just remove one or the other and tap in...

[frito-bandito]

Don't mean to butt in here, but which one would you hook up a mechanical guage to? IE Autometer?

I always hook up mechanical oil gauges to the one by the distributor just because its closest to the firewall, but furthest away from exhaust manifolds or steering shafts.