I have a 2005 Liberty w/ 86,000 problem free miles running biodiesel until this week. Feels like it is starving for fuel. Specifically it starts and idles normally, but when I accelerate at about 15 mph it loses power, can hear hissing noise, then accelerates to 15-20 mph and repeats. I've replaced fuel filters twice and found a pinhole leak in fuel line. Check engine light is on but can't get into dealer until next week to have the code checked and really don't want trust the stealer if I can get this diagnosed myself. Any help from those more versed in this sort of thing would be appreciated.

 

if u can hear a hissin, good chance u have a boost leak. im not to fimilar with the crd but from what i know bout diesels, most boost leaks cause a hissin/whistleing noise

 

It's hard to tell for sure where the hissin noise is coming from but I think its just the turbo gets spooling and then the motor dies. Sounds like the noise is from the exhaust rather than the engine area. Like i said it almost feels as though its starving for fuel, gets some and powers up, then repeats.

 

check the boost hoses the one from the turbo to the intercooler and the one from the intercooler to the intake manifold. They look like radiator hoses. These are prone to failure do to the fact that crankcase gasses are recycled back through the intake tract and engine oil also gets pulled through the trap. When's the last time you cleaned your MAP sensor?

check the fuel filter head also, the fuel heater on these tends to melt the housing allowing air to leak in. the way to check is, unplug the right(when looking at it from the front of the vehicle) plug and the pump the primer until it gets firm, then watch for bubbles or fuel leaking out around the pins. You might need a flashlight to see inside.

 

Haven't ever done anything except the routine maintenance(change oil, fuel filter, tires, breaks, you know). First sign of a problem and the little woman wants to trade it on a gasser(BS). Haven't touched the map sensor or egr which I have also read is a problem. Would they cause this severe of a symptom?

 

Does it smoke at all out of the tailpipe? If it does a lot then it is probably egr related, but the sound you described sounds like a boost hose leak.
On my wife's I had one leaking because a hose clamp wasn't tight enough, and that was enough to put into "limp mode" it wouldn't do over 30mph and no power.
The map sensors get "caked" full of oil and carbon from the egr and crank case gases. They are easy to clean with either carburetor cleaner or sensor cleaner. I personally use B-12 Chemtool carburetor cleaner. Just add this to your routine maintenance list. I clean mine every oil change.

 

Hmmm, having a bit experience with Jeep Diesel fuel filters.
recheck them again.
Make sure the rubber seal is covered with Diesel before you mount it.
It will leak air if not done!
Please tell us the diagnostic read out- it will be important for others in the future.
If air is in the system, it has to be moved out completly.
with 86kmiles your egr system shold be still clean.

It sounds like some air in the injector lines...

 

Found a crack in the boost hose and I have a bad egr. I found some info on the lostjeeps site with picks that were very helpful. Unplugged the sensor on the airbox which disables the egr and the jeep runs. Still had the hissing sound and found the crack in the hose on the drivers side. I also cleaned the map sensor which apparently should be part of the routine maintenance. Has anybody done anything to their jeep to eliminate the egr? I'm thinking about it.

 

I just leave the air flow sensor unplugged to disable the egr. You get a check engine light, but it easiest and cheapest. Another way is to get a SEGR kit it disables the egr without a check engine light. Green Diesel Engineering's tunes limit the amount of the egr. I am going to send my ECM to them as soon as funds allow.

oh yeah

 

The little woman will never go for that(leaving the CEL lit), but given the fact that the repair at the stealership will be $$$$$$ maybe I can talk her into it until I get a day to try and replace it myself. I looked at the segr thing but even if i did get one i dont know if I'd want to try and tackle that. Looks like a complicated wire mess to me. Maybe someone who has done it could share a little about whether it was as difficult as it sounds