Hi there, I'm fairly new to this site, I have used it for research before, but this is my first post. I am having trouble with my 2005 Jeep Liberty CRD stalling while I am driving it. It isn't overheating, and we know it's not the fuel filter or the head unit as i just replaced it a few months ago. I recently had the "Under Boost Condition" code pop up a while back, and I found out that the inlet hose from the turbo to the intercooler had a huge cut in it, so I got that fixed, and now the turbo is a lot quieter, and the "Under Boost Condition" code is gone. The Jeep doesn't stall as much as it did before, but it is still doing it, and I'm wondering if it might be a fuel injector problem, or a fuel rail pressure problem. I noticed when my rpm gauge drops to Zero, the Jeep will shake a few seconds after that, like when I turn it off. so I'm wondering if that is because of a bad fuel injector, or if it is losing pressure in the fuel rail. When the Jeep does stall, if I let it sit for a few minutes, about 8-15 minutes it would start back up again like nothing ever happened, but now that the boost leak is fixed it only takes about 3-5 minutes before it will start again. I have also been watching the Fuel Rail Pressure when I crank the engine after it stalls, because it will crank but not start, and i noticed that the Fuel Rail Pressure is only at about like, 1000psi max? it has been a while since i checked that while cranking it after stalling but I know it never got any higher than 1000psi while cranking, but after letting it sit, it would get up to about 5000-7000psi and it would start right up. While I am idling in park, or any gear really, the Rail Pressure is kind of jumps anywhere from 4800-5800psi, and I was wondering what the normal Rail Pressure is when it is idling. Also, when the Jeep stalls, the "Low Oil Pressure" light comes on and the dash makes a chime noise at me. This is only my third vehicle, as I am only 18 years old, but I also know a lot about vehicles, and I have a very strong passion for working on vehicles, and learning about them etc., but I still have a lot to learn, so any and all help and input is greatly appreciated.

I will let the experts here advise you on what the rail pressure should be.

I had a problem with my 2002 Export CRD suddenly grinding to a halt on a long trip....the Jeep would "ping" and the Oil Pressure light would come ON. No CEL codes were posted.

I could restart the Jeep after a minute and carry on for a few more miles and this would repeat...getting worse as I went along. I knew that my fuel filter was overdue for replacement so had a new Mopar one resting under the driver's seat.... waiting for the magic fairy to fit for me... so as soon as I reached my destination I drove straight to a Mechanic friend of mine who quickly installed the new filter for me and things have been fine since then

So maybe you are getting air into the system, have a bad or leaking fuel filter or do have a fuel rail pressure issue but the ping and oil pressure light would appear to be expected under the circumstances and a lot of fuel related problems do not post a CEL!

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2002 Export CRD

Yeah 1000 psi is definitely too low. 5000-7000 psi sounds more normal.

Often this points to a failing crank position sensor, but the low fuel pressure says otherwise. I would suggest air in fuel, but I don't think that normally "fixes itself" after a few minutes. But nonetheless, when it dies you could try pumping up the plunger on top of the fuel filter head, and then opening up the bleed screw (11mm wrench) to see if you get any air out of the fuel filter. You could also try replacing the fuel filter as Billybob mentioned; maybe it's full of crud and is restricting fuel flow.

Are you getting any codes?

This is totally normal. The oil pump is driven by the crankshaft so if the engine stops, the oil pump also stops and you lose oil pressure.