If it sat for a month and a half, I'm thinking a good possibility of microbe contamination/sludge, leading to a clogged fuel screen in the tank and/or a clogged fuel filter.

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Mitchell Oates
'87 MB 300D Diamond Blue Metallic
'87 MB 300D - R.I.P. 12/08
'05 Sport CRD Stone White
Provent CCV Filter/AT2525 Muffler
Stanadyne 30 u/Cat 2 u Fuel Filters
Fumoto Drain/Fleetguard LF3487 Oil filter
V6 Airbox/Amsoil EAA Air Filter
Suncoast TC/Shift Kit/Aux Cooler
Kennedy Lift Pump/Return Fuel Cooler

The dealer found the "fuel pressure feed line" to be leaking air, although I am unclear on exactly which section they were referring to (it's not the steel section; I suspect it's the section immediately leaving the tank module). Replaced and all seems to be good, w/seemingly more power than before. Took only 9 days too... (2 visits for 15 days total) The receipt indicates the purchase of the fuel tank module along with the fuel supply tube & fuel return tube, so maybe more was replaced than the service advisor knew or cared to discuss. I have no idea why it would have involved the return line. In any case, I'm glad this is apparently fixed. I'm at 10,000 miles now & satisfied with this having been my only problem thus far. No other glitches, plenty of power, & 30 mpg on the freeway. We'll see how it goes here on out.

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2006 Jeep Liberty Limited CRD w/275000 miles

There is still another possibility and that is faulty wiring. Several here have experienced that and I think all were 2006 models. There are a couple of places the main wiring harness will rub and one of the problems it creates when the wires fray is the CEL you are getting. Run a search and see if you can find the earlier topics about this same issue.

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Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

My '05 CRD (33k miles) has always stuttered a little bit after a brisk acceleration onto a highway. Usually lasts 5 to 15 seconds of steady speed before it gathers its wits about itself and run smoothly again. THAT has always been the case and I'm okay with it. Just one of the cars little quirks that make is special.

Until today...

This morning after about 12 minutes driving on surface streets, I sped down an interstate onramp at WOT to fit the little CRD into an opening in traffic. Just as I let off the throttle and pulled into the lane (in front of an 18 wheeler of all things) the stuttering began and quickly grew into a harsher bucking effect. It lost power and felt like the engine had been shutdown. I feathered and pushed the throttle pedal a bit, but could coax almost no power out of the engine. I coasted along (horns were blowing at me by now) and took the next exit ramp, coasting to the stop sign. The little diesel was still running, but felt like it was firing on a single cylinder. No smoke - no harsh sounds or anything else out of the ordinary - just a near total loss of power. Even stepping on the throttle in neutral brought a VERY, VERY PAINFULLY SLOW response as the rpms slowly climbed toward 3000 or so. I let it idle and put it back in gear and it would barely pull itself out of its tracks. Luckily the road was slightly downhill and I got it up to ~30 mph and she would hold that speed - but not accellerate much beyond that. No CEL lamp - nothing to indicate a problem except the loss of power.

Wheeled into a parking spot and left her sitting for a half hour before going back to get her. Turned the key and she fired right up quite normally, smooth as ever, and has full power. You'd never know it had been a problem at all. Drove it back onto the highway (not WOT this time though) and she ran perfectly for a 10 mile test romp. Not once did she even stutter. Ran as good as she ever has!

Having read several others' experiences with this sort of thing, I have developed a theory. The only ECM code anyone has reported was related to a loss of fuel pressure. Perhaps that means the high pressure fuel rail? If so, I wonder if it is possible that at WOT and high RPMs the fuel pump just does not deliver sufficient flow to keep the pressure up. Sudden loss of fuel rail pressure would conceivably trigger the ECM into "limp home mode" to prevent damage to the engine and injectors. This could easily cause the symptoms I've seen. And given time to sit the ECM would reset for another cold/warm start cycle which would rememdy the prior problem. I'm not a diesel engineer (but I am a mechanical engineer!) and this theory seems plausible.

Its only a theory. But for now its all I've got. Anyone else know of a more likely cause? And is there any known fix? I've had every TSB done up through about 3 months ago.

This little CRD is running so well I hate to put it back into the hands or my local dealership. They've mucked things up a couple of times on simple things (left off the oil drain seal, etc.) and its hard to trust them on something this confounding. Yet, I am keenly aware that my 36k mile warranty is soon to catch up with me. No telling if they'd cover this sort of issue on the 7yr/70k powertrain warranty.

i had the exact same symptoms back to back after two fixes, but I'm a gasser KJ, so I dont think it relates. Mine were crank shaft position sensor and drive train position sensors respectively, going out on two back to back weeks. gave me the same EXACT symptoms though as you describe.

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2003 Silver Sport - Debadged
245/75/R16 DuraTracs
Cragar Soft 8s
OME Coils & Front Shocks, Bilstein Rear Shocks - Muddified Lift
JBA 4.5 UCA
K&N CAI
MagnaFlow Exhaust
Rola Vortex Rack

http://www.fusion-multimedia.com

My experiences match yours exactly, except I have also had the "fuel leak, large" code show a few times and it has outright died on occasion (all following full throttle, normally when climbing a hill or loaded a bit). It still happens since the dealer replaced the fuel tank module & the initial section of line, but only with some percentage of biodiesel in the tank (any percentage). I have usually waited only 30 seconds or so following shutdown to have it restart in normal mode with full power, but I have had to wait longer on occasion after restarting to find it still in limp mode. There is no fix that I know of. Your theory sounds plausible, however, I wonder if it could accommodate the fuel leak code in my case, or the fact that my situation distinctly improved with the replacement of the tank module & fuel line section. Is there a code specifically triggered by a loss of rail pressure? I don't recall but if so, then I wonder why it wasn't triggered, and why, in my case, a fuel leak code was triggered. But, its feasible we have different problems. I wonder if we could see more of the real symptoms if limp mode wasn't triggered. It'd be nice to be able to unarm it somehow. I still suspect a simple leak to be the cause, especially given the code and improvement. The one thing that I've wondered about, however, is that it has died or gone into limp mode within just a few seconds of stomping on the pedal, maybe even as soon as 3-4 seconds (if I recall correctly). Could an air leak cause such an effect so quickly, being that it must occur prior to the pump? Anyone know how the computer detects an air leak? Is it just sensing a change in line pressure? Anyway, good luck! Please post any developments.

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2006 Jeep Liberty Limited CRD w/275000 miles

Hawk

First if you didn't have a cel it's pretty clear by now that you did not go into "limp made" My shudder and lousey trailer towing were cured when I put a lift pump on Did you shut it off and restart before leaving it sit? It was determined back when DRVHD had a bad ingection pump that the CP3 does several things when starting and one is to let the air bleed out of the pump! I suspect your problem is from air in the fuel head and lines. There is no simple answere here but I would like to think that when Chrysler does a recall for the leaking fuel heads the problem will be taken care of One can always dream

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

Bio and Joe,

While I did not get a CEL lamp I can state categorically that it "acted" similarly to what I would call a limp home mode. It would idle (very roughly - felt like it was firing on one cylinder). In neutral it would VERY VERY slowly rev up when I depressed the throttle. Had almost no torque and was very sluggish.

Initially when I shut the engine down I tried to restart it a few seconds later. The battery cranked it over just fine, but the engine would not continue to run w/o the starter motor assist. Only after cranking it continuously for perhaps 25 to 30 seconds did the engine finally start - and then it still seemed to be only firing on a single cylinder. At that point I fully expected it was going to need towing to the shop.

I parked it and went back later and it fired up normally as if nothing had ever happened.

I cannot explain the lack of a CEL lamp. But I it sure seemed like "something" in the ECM caused the loss of power. As I mentioned in my first post - this stuttering after hard acceleration has existed since my CRD was new - happened every time I went WOT for more than a 2 to 3 seconds. But this was the first time the stuttering, stumbling did not recover on its own within 10-15 seconds. Fortunately a shutdown and wait period resolved it this time.

Hey all-in-all I'm not complaining. I love this little diesel. Mostly I posted my experience in the hopes that there might become a body of evidence large enough for the folks at Chrysler (or VM Motori) to recognize the symptoms and offer a fix. I suspect they could do so if so inclined. I still believe the symptoms are self-inflicted (since I can reproduce this effect) and are the result of some ECM firmware that is probably aimed at minimizing damage to the engine under duress (WOT?).

Hawk

While the thing acts like computer induced "limp mode" this is what most of us believe to be air in the fuel. It never throws a CEL that I can determine. IT goes away if you shut down for a bit then re-start.

The source is an air leak in the system or possibly, under high heat conditions, tiny air bubbles in suspension in the fuel that come out of suspension when fuel is sucked under negative pressure to the injector pump and gather at the highpoint in the system (The fuel filter).

See that all the fitings on the filter are tight and the fuel heater plug is not leaking. See if there are leaks around the plastic puck between the filter and the filter head. Bleed the air. If none of that works consider a lift pump near the tank and a filter head replacement.

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Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

No leaks anywhere in the fuel lines or filter. Dry as a chip under the hood and I've never seen anything (other than A/C condensate) drip from the Jeep in my driveway. After some 29 months and 33k miles there is a little dust on the engine - but quite frankly, I'm amazed that the engine compartment is as pristine as it is - especially for a diesel. A whole lot cleaner at this stage of its life than any other vehicle (gas or diesel) that I've owned. As messy as a diesel leak can be, I'm pretty confident there isn't any fuel getting out.

Now whether there is an air leak into the fuel system - that's certainly something that I have not actually considered. I'd have thought that the CRD would have an electric pump imbedded in the fuel tank to force-feed fuel to the engine's fuel pump. But maybe not... Anybody know?

I don't recall the fuel filter ever being changed. Not that I recall anyway. Seems to me that if air was getting into the fuel the problem would not self-correct... Or are you suggesting that maybe it only happens at WOT conditions?

I'd like to better understand what you think is happening. Air is compressible whereas diesel is not (for all practical purposes). But if it was air flowing to the injectors - wouldn't letting it idle for a few minutes flush the "air" through and self-correct the problem? Surely air would flow through the injector just as readily as fuel - even more so. This could explain a momentary loss of power due to fuel starvation - but unless there exists a replenishing supply of this air, it would auto-clear in rather short order would it not?

Not arguing with you - just trying to figure this thing out. At any rate, I'm not too worried about it. Since the situation is avoidable and even if I encounter it, I know how to get past the problem, it is just another one of those CRD quirks that I'll have to grow fond of I reckon! lol

-Hawk

hawk521

you need to read some of the Fuel threads - the CRD fuel system is a vacumn from the pump at the engine to the tank.

To fix the constant problems some folks have (not all by the way ) - they've added lift pumps and new filter heads.

http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?t=23117

http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?t=25537

Because it's very difficult to troubleshoot a vacumn system - dealerships are generally clueless. and typically can't reproduce the problem.

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

There is no lift pump in the tank. This is a suction-based system. The lift pump is incorporated with the high-pressure fuel pump in a single unit. The fuel is being sucked from the tank at bottom, rear of vehicle to the high-pressure fuel pump at the top, right, front of the engine.

If you were to have fuel leaking out, then I would expect a lot more air to be getting in, which I'm sure you'd notice in the form of abnormal operation. There are two codes that can be triggered by air leaking in: "Fuel Leak, Large" & "Fuel Leak, Small." I've had the first appear 3 times. It automatically resets after a number of warm-up/cool-down cycles.

There has never been any evidence whatsoever of leaking fuel on mine, from tank to pump, but I've yet had this limp mode/dying engine problem since 2200 miles (although it hasn't happened for about 10000 miles now, since I simply avoid full throttle when running on bio).



I'm convinced this is what's happening with mine. It only happens when I'm at full throttle for a few seconds or more. However, it was quite a bit more frequent & easily induced before the dealer replaced the tank module & line section, especially on long climbs. I'm guessing there must have been multiple leaks and that the dealer's action decreased the amount of air leaking into the system to the point that it normally isn't enough to cause problems.



I assume the cause of my engine dying on occasion has been fuel starvation, but I really don't know. It normally happens without any warning. There have been a few times that it shuddered for half a second to a second before shutrting down. I wonder if air thru the injectors is really the cause, since it seems to happen so readily. Maybe sufficent air thru the high-pressure pump causes a significant drop in rail pressure that results in insufficent fuel injected or poorly injected. But, then, wouldn't the computer pick that up? Maybe it takes multiple events.



Same here!



Mine has gone into what I have called limp-mode at least 50 times, and only 3 times (including the dozen or so engine dying events) have I had a CEL come on (although the CEL was already lit for a number of them of those, maybe half of them). BTW, the only DTC that I've been aware of is "Fuel Leak, Large." The experience is very consistent. (1) WOT for more than a couple seconds, (2) very brief or no shudder, (3) loss of power accompanied by loss of any turbo whine and a locking of the tranny in gears 1-2. There usually is no warning whatsoever or one or two minor shudders before the loss of power, however, I did have shudder last upwards of a couple seconds on occassion (only during long climbs, I think) before the dealer replaced the module/line (I haven't had extended shudder since). Any shudder has been very light (could miss it if not paying attention) with a few incidents in which it was a little more violent but not to the point to give me whiplash or make me think the tranny was taking a beating. The engine suffers a dramatic loss of power that limits it to 40-45 mph at WOT on level road. The torque is gone, the rpms come up slower than normal, and there is never an turbo whine. However, the engine continues to run nice and smooth. I've never detected any roughness. Also, the tranny has been locked into gears 1-2 every time. However, if I am in 3rd or 4th gear when it happens, I can continue in 3rd or 4th gear so long as I keep my speed above 35mph or 53mph (can only keep it in 4th while going downhill). I am locked into 1st & 2nd once it downshifts. As far as I can tell, I can drive in this condition for as long as I wish. My longest stretch like this has probably been 5 miles or so, while trying to find a good spot to stop (it can be a while on mountain roads).



Usually, I can restart within a minute and it starts & runs as if nothing ever happened. However, there were a few occassions back when it was at its worse that it took a little more cranking than normal, but nothing like 30 seconds of cranking.



As i mentioned, the vast majority of my incidents have failed to trigger a CEL. Also, I haven't had this stuttering that you describe. It goes more along the lines of:

running smooth while accelerating hard=>litlle or no stutter/shudder=>running smooth with no power , or
running smooth while accelerating hard=>little or no stutter/shudder=>dead engine

It runs smooth following hard acceleration if the above doesn't happen. However, I do recall maybe 2-3 instances of brief shuddering (1-5 shudders) following hard acceleration without anything further. This hasn't happened lately tho.



Joe, I haven't been keeping up, which pump did you go with? It seems like that's the way to go. How many miles do you have on it? Any problems? I remember that DC engineering student recommending not to go that route last year, although I think he acknowledged that their problems may have been unique to their set-up. A lift pump makes a lot of sense to me, but then I'm not an engineer.

Mike

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2006 Jeep Liberty Limited CRD w/275000 miles

If it's not limp mode I think we should call it WIMP MODE.

It happens often enough to have its own name.

Joe, I haven't been keeping up, which pump did you go with? It seems like that's the way to go. How many miles do you have on it? Any problems? I remember that DC engineering student recommending not to go that route last year, although I think he acknowledged that their problems may have been unique to their set-up. A lift pump makes a lot of sense to me, but then I'm not an engineer.

Mike

Mike.
I got one that comes on at 4 psi, off at 7 psi and 32 gallons per minute at napa and it was under $50 with fittings. It's a napa brand of the pump BlackLiberty used. I stuck the plus wire in the switched pin of the socket for the "primer pump" relay and the put the relay in. (pin 5 as I remember per BlackLiberty) I tye wrapped it to a wiring harness just behing the battery. Ground lead is piggy backed to the ground cable on the battery. It came with a small prefilter. Input to the filter now goes to the pump and the pump output has a hose to the input to the filter. No bypass or anything.
11k total on the crd and about a thousand with the pump. No smoke, no bad manners, it just goes The full throttle from a stop delay is mostly gone. I even plugged the MAF in and cleared the CEL and it still runns fantastic MrMopar's experience indicated it caused problem but to my knowledge no one that's added a pump has had problems. Also everything is added to the "dirty" side of the filter so that avoids the potential for contamination. I installed mine for easy removal if it needs to go to the dealer for anything but the ideal place would be back by the tank. I'm kind of waiting/hoping Chrysler comes up with a official fix when the dust settles on the fuel head A person can dream
Joe

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)