Ok, here’s the deal. My S/O has a 1999 (i’m pretty sure) Jeep Wrangler. The Oil gauge has a “40” a “60” and an “80” mark. It usually reads betwen 40 and 60 in gear. It reads 60 when the Jeep is idling but now when it is in gear, it reads between the 60 and the 80. What is happening? How worried should I be?
It’s not due for an oil change for another month or 500 miles. It has not been off-road. Any help is greatly appreciated as money is a bit tight right now.
Thanks all.
Did the oil pressure change suddenly or has it always been like this? Consider that the oil gauge may not be accurate as it may have gone out of calibrations. If it is accurate it could indicate a problem. A clogged oil passage could cause pressure on the output of the pump to go up. It may not cause damage until one or more bearings gets starved then things could get very unpleasant. If could possibly be a clogged filter but most have a high pressure bypass. An oil change now is cheap and can’t hurt.
Yeah, it just started yesterday.
So if we get the oil changed/oil filter changed…this will probably take care of the problem? What’s next if that doesn’t do it?
I don’t think that’s quite what Padeye wrote. It’s possible that there is a clogged oil line but that’s by no means certain. Check the oil on the dipstick to see if it is dirty (really, really black) or just a little dirty (semi-clear, if that makes sense). Is the oil changed pretty regularly? Like every 3 or 4000 miles?
If it happened suddenly it could be the oil pressure sending unit. That’s a gadget that screws into the side of the engine with a wire that goes up to the dashboard gage. If you have a manual for the car it will probably tell you what the resistance of the sending should be when the engine is not running and when it is.
The gauge may or may not be reading accurately. You might have a pressure problem, or you might have a gauge problem. Your options:
Have the oil changed now and see if it makes a difference. Not likely, but not impossible, and you’re going to change it soon anyway.
Replace the sending unit and see if it makes a difference. Reasonable chance, but it’s a gamble.
Have it tested. The first thing I would do is test the oil pressure with a mechanical gauge to get an accurate reading. If the pressure is indeed high, further testing would be in the engine mechanical area. If the reading is significantly different from what the dash gauge shows, further testing would be in the gauge system ( = sending unit, wiring, gauge itself).
Further thoughts on the OP:
Its reading higher in gear suggests an electrical (gauge system) problem. (By “in gear” I assume you mean sitting still idling, not driving along.) Normally the reading goes up somewhat with engine speed, so a slight variation that coincides with an engine idle speed change would be expected, but if it suddenly goes up 20 psi when shifted from neutral to drive, I’m thinking a partial short circuit or faulty connection might be getting affected by the shift linkage or the engine leaning.