oil pressure display not showing

[mutley]

Hi. My oil pressure display stopped working all other displays work just not that. does anyone have any ideas ? if you think it maybe the oil pressure switch , where is it located.. 88 c4 5,7 auto all help appreciated. thanks in advance.:ugh

 

[68 4 spd]

oil pressure switch is on top of engine in rear by distributor to the left you dont say if the reading is at 0 or not lit but if the car runs and gauge is not reading it probably is just a bad sender hope it helps:cool

 

[boomdriver]

Look on driver side head on backside where you cannot get to it...thats where it is.

There are 2. The bell shapped one is the pressure sender. One wire to that. If the connection is bad of loose the pressure will be 80 psi all times. If the sender has failed it might show 0 or sometimes stuck on some random number. They operate on varying resistance signals.

The 2nd sender is the fuel pump safety switch...or back-up switch. This one is the back-up system for the fuel pump relay. If the FP relay fails the OP switch will send power to the fuel pump as long as there is 4 psi oil pressure, or more. Some folks theorize that GM also uses it to cut power to the fuel pump IF there was no oil pressure, but that can only work IF the FP relay was d/c.
That sender/switch has 2 wires to it and should not be involved in gauge readings.

Last option would be a faulty display. 9/10 times its the OP sensor. You might want to check the one wire to see if its grounded somewhere. Thats a good possibility as well.

 

[mutley]

thanks for the info boys.... Ive sorted it out now , it was the oil pressure switch on the dash .. but now i have a problem with the heater controls ... better start a new thread i suppose.