WHEN I START MY 1999 GMC JIMMY THE OIL PRESSURE ...
1999 GMC Jimmy
April, 20, 2011 AT 11:33 PM
When I start my 1999 GMC Jimmy the oil pressure gauge spikes up over 80 and stays there. Oil is fine and recently changed. How do I tell if I have a bad oil pump or oil pressure snding unit or a switch or other malfunction?
Best place to start is by measuring the pressure with a mechanical gauge to see what you really have. I'd suspect the sending unit first but for a quick check, unplug the connector from the sending unit. If the gauge stays at maximum, that wire is grounded somewhere.
April, 21, 2011 AT 12:07 AM
Checking the pressure with a mechanical gauge is a good idea but with the labor time involved to do that, it may be cheaper and easier to just throw a new sender on it. It's cheaper than the labor time.
April, 21, 2011 AT 1:51 AM
Is the oil pressure sending unit easy to replace and if so where is it located at?
April, 21, 2011 AT 1:55 AM
That one should be in the back of the engine, next to the distributor. It just threads in but you may need a special socket.
April, 24, 2011 AT 8:58 PM
I took off the air intake and the distributor off and got to the oil pressure sensor to find that it was unplugged. I plugged it back in and that fixed my problem. Thanks for your help.
April, 24, 2011 AT 9:00 PM
I wish they were all that simple.
April, 24, 2011 AT 10:15 PM
No kidding. That choice isn't even on my dart board!