Hi,

CRD 2.8 12/2006, automatic, about 180 thousand kilometers on the clock (110 tmiles). Used in proper winter conditions in Finland.

I have a strange intermittent problem. Sometimes (maybe between every 500 miles), when I start the car, it starts normally, then when I get going, the engine lacks power, won't rev properly, stalls or almost stalls, and some black smoke comes out of the exhaust. It feels almost like something was holding and trying to stop the crankshaft, or like the fuel supply was cut as soon as I push the pedal.

After this happens, the engine has always started immediately after quite normally (may require an extra turn or two when starting), but may also stall again. When I let/get it running at idle for a while the issue goes away, and it's like nothing happened. Not even fault codes or warning lights.

I can't connect this to any driving style or anything else either, except I think this happens more likely when there have been sudden temperature changes, like from +5 C to -10 C overnight. I have noticed that this could happen when temperature has recently dropped, but today it also happened when temperature rose from -26 C to -14 C in less than a day. My first thought was if it was due to moisture condensing in fuel line or elsewhere.

So far I have changed fuel filter, air filter, (engine oil & oil filter), and cleaned the MAP (boost) sensor (no dirt found). I also checked for blown head gasket, but that seems OK. Anyways, the problem still exists.

I wonder if it could be a blocked oil circulation in gearbox (automatic), AC compressor, or alternator feeding the glow plugs and pulling the power off the engine… Or a sensor… Or moisture somewhere…

During the summer time, I got a low boost pressure fault a few times, but that has not happened after autumn. No real fault found there either, but turbo has not been off the car. Maybe this is somehow related, but I have a feeling it's not. Low boost pressure should not stall the engine, it should just lower the power, right? And in the recent fault, no boost level pressure fault code appears.

Any suggestions?

You have not mentioned the EGR system, and your symptoms sound like ones indicating a faulty / leaking EGR or FCV solenoid(s). If no problems are found here, proceed to the Vacuum solenoids/hoses controlling the turbo.

Do you hear any new / unusual sounds when the problem presents it's self?

_________________
'06 Lbrty Sprt CRD 150K

Sasquatch
DSS Turbo
CAT-elimntr
Weeks Stg1&2 EGRfix
PV-200
BLING
vent gauges

IDParts
head
cams
rockers
Timing set
ARP studs
eTn1 GX2123 5v GPs

YETI Custom Tune
Flowmaster 8325508
Carter P76611M
GM 12611872
Hayden 2986
GM 15976889
PATC Custom Billet
2010 Ram Hemi Trans
Sonnax 44957
Transgo kit
Cooper 51770

The EGR system is in place, and I haven't disassembled it yet so I obviously need to check it then. FCV valve I haven't touched either yet. Turbo hoses and solenoid I did check in the summertime when I got the low boost pressure codes.

No strange noises during the fault, but the thing is pretty loud in any case.

Thanks for the tips!

Could a faulty Crank Shaft Position Sensor (CPS) be part of the problem? Some of the symptoms (eg. start then no power, can't rev, etc.) was cured when I replaced CPS. Did not show any fault codes.

_________________
Ludi Neethling
South Africa
2005 Jeep KJ CRD 2.8 (6 M/T)
Susp:Ironman Coils, Shocks new bushes and ball joints
Therm: Replaced
EGR: Cleaned, re-installed
CCV Catch Can
MAP sensor: Cleaned
Injectors: Repl
Alt pulley: Repl
Serp Belt: Repl
Crank Pos Sens: Replaced
T/B & W/P: Repl @ 200k Km
Repl Cer GP with Etechno 7V GP 212k Km
Repl CCV

Answering to myself for archives, and whomever reads them...

This fault disappeared by itself. Without further checking the EGR or FCV, just driving and normal maintenance. No glue what it was. (I get CEI every now and then and the low boost power code, but that now seems to be a different fault and most probably related to the EGR system or sensors as proposed).

And to close the thread: the remaining CEI issues and code for low boost disappeared after repairing the EGR (valve replacement + cleaning + fixed intake leak in the elbow connecting the FCV to intake manifold). And I got noticeably more power also due to fixed intake leak...

Have to say the parts are located really awkwardly, especially the valve and elbow bolts. Many hours of fiddling with mirror and going up in engine bay hanging over the engine and back underneath the car. Easy to understand those who just remove the EGR. I didn't want to do that due to uncertainty of whether it would pass the local MoT without EGR, or not. Apparently it would have, but now it's fixed anyways...

If you can, the very best thing you can do for your motors life is to totally remove or at least block off the EGR system.
(Drawing of EGR block off plate shown below)
They are a known engine killer due to making mud soot pies in the intake manifold and contaminating engine oil (soot loading) along with particle blasting the valve stems. See images below.

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve