Just trying to figure out why my oil pressure gauge bounces? 86 Iroc, 305 tpi, It will stay steady for a couple of sec then it bounces up and down then back to normal.....Thanks for any and all help

 

see what happens with a mechanical gauge. i had a metal shaving get into a main bearing a chewed it up and caused the same problem.

 

Check it out as stated above.Mine has been doing that since I bought the car.Like 7 or more years ago.

 

is it doing this in while stopped in drive? They will bounce a little bit if your at lower rpms, maybe 5psi or so. It should be steady under a load, could be a bad connection too

 

I replaced the gauge in our shop truck for the same problem and the bouncing went away

Oops, meant to say sender

 

Yes, it only does it at idle. Under throttle it seems to be steady. I just had tach/oil gauge recalibrated . Bad connection where? Could it possibly be oil p/s switch?

 

check the sending unit. if it is a TPI there will be a solenoid by the distributer, it looks like a fuel filter, its a $10 fix and takes 2 mins to change. my oil pressure dropped to nothing. i changed it and had no further problems

 

sounds like u need a oil pressure switch. i had the same thing with my 91 camaro. u can check it by if you have a new oil pressure switch on hand. unplug ur old one and plug it into the known good unit and ur oil pressure should be at 0psi cuz it not bolted to ur block. if it reads 0 even when u rev ur car then its you oil pressure switch.

 

does it affect how the engine is oiled or how it runs?

 

The safest thing to do is ck it with a known good mechanical guage.It could be the sender,bad guage,bad ground,loose connections.It could also be the relief spring in the pump trying to stick.If it cks good w/ a mechanical,you know it's external,sender,wires,etc.It shouldn't cause drivability issues tho.

 

Just change out the sending unit.

Don't bother with a mech gauge. All you will end up finding out, most likely, is that it needs a sending unit. 90% probability or greater.

Meanwhile, if changing out the sending unit doesn't fix it, then you still don't need a mech gauge, because now you can trust the factory one. BUT, you're only out $15 and a coupla minutes work, instead of whatever dinking around a mech gauge would have required.

THINK: 90% probability, $15, 30 seconds, EEEEEEEZY, car is FIXED; compared to .... what?

Oil pumps basically don't fail in these engines. Springs don't stick. It just simply ISN'T anything to do with the oiling system itself.

 

Listen to ^^this^^ guy. Just a good mix of understanding how "things" work, common sense logic, and experience with cars.