Question about 2004 Jeep Grand Cherokee
When I am sitting at idle, my oil pressure goes to zero. I just had an oil change and there are no leaks. What could be the logical problem.
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
Here's a link to this great service
Posted on Jan 02, 2017
u Have a problem with the oil sending unit. The sensor is located beack right side of the engine block. Take out the switch and make sure u have good oil PSI. Should be 6 psi at idle and around 50 at 4000 RPM. If the presure is ok replace the switch they are very cheap about 20 bucks. Please rate.
Posted on Aug 12, 2009
Two things...when it reads zero, is there any engine noise (tapping or knocking)? After you rev the engine does the pressure read normal at idle and function normally, or does it go back down? Either way, you should not drive the vehicle 'till you have a mechanical gauge (yours is electro-mechanical) put on there and the actual pressure is tested. The condition may be a bad sending unit, a bad bearing or possible obstructed oil pump screen. The repair is obviously different for each one and the price is as well.
Posted on Oct 20, 2009
This has an electric pressure gauge with a sending unit. Try this: When at idle, SLOWLY increase the engine speed. If the needle on the pressure gauge all of a sudden leaps to a pressure (like 'real quick') and acts normally with even faster engine speeds, the sending unit is bad. (It is just not reading the lower pressures.) Zero engine pressure will manifest itself in a bunch of knocky sounds and lifters that aren't pumping up and therefore "ticking" loudly. You probably don't have that since you didn't mention these problems.
Replace the sending unit after the above test and you should be fine.
Posted on Nov 24, 2009
Testimonial: "Thank you. you may have just saved me a lot of time and grief"
The first thing I would definitely do there is change the oil. Used oil tends to loose lubricity and becomes thinner than it was when in the container. When hot, it becomes even thinner and will cause a drop in pressure.
Most jeep engines hold around six quarts of oil, so by adding what you did the new oil helped a bit but cannot correct the problem.
I would change the oil and use either a 20w50 oil with a pint of Marvel oil, or change to a good synthetic with a container of Lucas additive. It is possible that whatever oil you have been using is causing a carbon buildup that is beginning to block off the pump pickup screen. Either of the above suggestions will help with that. In engine oils, price is important...cheaper oils are high paraffin base which causes deposits to form.
You don't want that in your engine. Only exception is Wal-mart store brand oil which I believe is Quaker State (re-packaged). If you opt for a synthetic, it's not a bad choice and is cheaper.
Make sure you use a good quality filter. The filter is what keeps the oil clean and useful during its lifespan.
One note... If there is any tapping or knocking inside the engine, that is caused by internal bearing wear and should be corrected immediately. No oil can compensate for internal pressure loss and if caught early, can be repaired. (otherwise, later, engine will need to come out and be overhauled or replaced.)
Any pressure problems can be verified by installing an external mechanical gauge on the engine. That is the only way to know exactly what is going on with any degree of accuracy. (dash gauge is electro-mechanical).
Posted on Dec 18, 2009
Testimonial: "Thank you SO very much for replying so quickly. Money has been so tight and with Christmas next week it just makes me sick to think of car trouble."
Tips for a great answer:
Jul 20, 2014 | 2004 Dodge Ram Pickup 3500
Aug 05, 2017 | Chevrolet Blazer Cars & Trucks
May 14, 2012 | 2004 Chevrolet TrailBlazer
Nov 19, 2011 | 2007 Dodge Ram Truck
Feb 02, 2011 | 2001 Jeep Grand Cherokee
Jan 10, 2011 | 2002 Chevrolet TrailBlazer
Mar 30, 2010 | 1996 Jeep Grand Cherokee
Dec 09, 2009 | Oldsmobile Bravada Cars & Trucks
Oct 20, 2009 | 2002 Jeep Grand Cherokee
Jul 15, 2009 | 1994 Isuzu Rodeo
329 people viewed this question
Usually answered in minutes!