2001 XJ 4.0L Oil Pump Failure. WTF?

"matt borland" wrote in

Wow, I see I've been away for awhile. No free lists anymore and redirects to Autozone for parts...

No oil pressure TSBs for WJs of the same vintage...

Hmmmm....

-Matt-

L.W. ("ßill") Hughes III did pass the time by typing:

Only thing that pops into my widdle mind is the pickup tube falling off but that's not very likely since IIRC it's got a bolt holding it into that engine. Howmever... You could pull the distributor and check the drive spline just be be sure. That will let you see the pump gear.

You could also be seeing a fault in the electrics, like a loose battery cable. but I don't have any info on the 2001. I have had a similar thing with tick/ping/etc and it was due to a loose battery cable.

I also wonder if the newer compooter will put the Jeep in limp mode based on oil pressure. Any codes?

As Bill says, the drive mechanism can break. I have also seen the oil pickup break off and fall into the sump. If you stopped when there was only ticking from the top end, there is the possibility that you saved it.

This could have been a plain old defective part, and there may be no TSB. My advice is pull the pan, pull the pump, and try to figure out what happened.

Earle

The one thing nobody remembered is the '01 is distributorless ignition...

But yes, I agree it must be the pump. Like in SBC engines the pickup (if press fit) can fall off or if they use a plastic bushing on the pump drive shaft it can let go, or I may have got the 1-in-10,000 bad pump...

Here's hoping the lag time between the light coming on and me noticing the noise/guage reading wasn't enough to toast the bearings or ruin the cam and lifters...

What a pisser...

-Matt-

Should be fine. I lost ALL the oil out of my celica's 22RE about 5 miles from home. Drove gleefully all the way with no damage. Still runs 10,000 miles later.

Carl

matt borland did pass the time by typing:

Distributor or not, is there still a pickup? Something has to be turning the pump and providing TDC reference.

Haven't looked that hard at a newer engine.

When mine went last summer it was as simple as the thin paper gasket between the pump and the block blowing out - but that left me with about half pressure, so I made it home. Outside possibility would be a high pressure relief valve stuck open or with a collapse spring. I would try pulling the distributor as others suggested first but you're probably going to have to pull the pan anyway. Good news is that it's a one bananna job to replace the pump once the pan is off.

Here's h> As Bill says, the drive mechanism can break. I have also seen the oil

Could it be a blocked oil filter or oil pump pickup screen? Are you using Fram filters??? Let us know what you find! later, dave AKA vwdoc1

Thanks to everyone who replied.

Mystery solved! The cam position sensor sheared the drive gear (as Bill suggested) and jammed up the works.

Everything else is fine since I got it shut down so quick.

I'd have shut it down immediately if it hadn't taken 20 seconds or so to convince myself that my 48000 mile Jeep was indeed showing no oil pressure and ticking.

As for the oil change questions I use Napa filters and this trip I tried the Mobil 5000 mile stuff. The oil has about 3200 miles on it and while it does look pretty clean it still smells gassy and looks a little thin so I'll be changing it sooner rather than later. I bought it because it was on sale and Mobil is usually good oil, but I won't be extending my change interval using this stuff... A true synthetic, sure I'll go 5000 miles on a change but not this...

Thanks again for the input.

-Matt-