I am still having problems, I have difficulty starting sometimes and a rough idle, seems to e worse when the engine is warm, often won't restart when warm and rev counter seems to jump around. I have run diagnostic only two codes recorded, one is a glow plug fault and the other a P0401 which I believe relates to EGR. I have had the EGR off cleaned it off as it was sooty, the diaphragm works, also the vacuum pipe is sucking if I pull it off and put my finger over it. The fault code cleared and hasn't come back so that isn't it. Anybody got any other ideas what could be causing issue I am seeing?
 
So I don't think its a sensor out I get the following readings during idle after cold start:

Air temp 3 deg c
Airflow 440-463 mg/fire
Manifold pressure 96-97 kpa
High pressure fuel 32000 kpa
Low pressure fuel 402 kpa
Battery 14.047 volts

The fuel pressure looks right, not sure on airflow and manifold pressure. All change sensibly when you rev the engine but don't seem to deviate massivly even when the engine is struggling to idle nicely. During testing this morning it cut out during idling. Can't find any other errors saved apart from glow plug relay. The scanner I have doesn't tell me anything on injectors or cylinders so can't see if the issue is a faulty injector or injectors due to pipe debris getting in the injector, other thought is the injector wiring. Any comments would be appreciated
 
If you had electrical problems on the injectors the ecu would see it.
If you have a mechanical issue on Injectors the ecu won't pick anything up.
 
Surely if it stalls the ECU should record it and freeze frame data? Think my scanner is confused by the year of the car so doesn't display any freeze frame data. Anybody tried iCarSoft LR V2 on a 2006 td6 in particular to investigate injector issues?
 
So the problem continues, I did a leak off test hoping one or more injectors would show up faulty. All injectors seem to leak off the same. Did a four minute test alternating from idle to 3k rpm and they leak between 32 and 35ml. 3 minute test just at idle was 15 to 18ml. Not sure if this is normal or not?
 
With engine running leak off should be below 20 ml @ 2 min on each injector at idle, though a small deviation from that is OK.
 
Thanks for the info Saint.V8 doesn't sound like an injector fault as it was less than 20ml on each injector after 3 minutes. I am now at a loss as to the fault, fuel pressures all look right, I swapped the MAF and cleaned the EGR and checked it is operating OK. The fuel pump is new with new solenoid valve, I have also changed all the filters, oil and coolant.

Really don't know what else could cause the hard starting and really rough idle, which now seems to be all the time even when cold. I also noticed white smoke when I last went out for a test drive and accelerated hard.
 
Today took out the injectors and had them tested, they all passed. The engineer that tested them said they were showing their age but we're OK and wouldn't cause the rough idle, also unlikely any debri got into the injectors due to the small bores in them and the pressure the fuel is under.

So not injectors, the mystery continues.....
 
You've had the high pressure pump off?
Did you check the fuel metering valve for debris also?
Does the pump under the car and the intank pump both work?
I'm not sure if there are two pumps like BMW on the l322.... Maybe à pump has failed and your suffering from fuel deprivation.
 
Thanks for your comments, the high pressure pump is a recon and had a new fuel bleed off solenoid on it so I have to assume it is good but as the injectors and air in let manifold are off I will check it to be sure. I think the fuel pressures look right.

High pressure fuel 32000 kpa
Low pressure fuel 402 kpa

The above figures are at idle and don't deviate when the idle is hiccuping so not sure it is fuel starvation causing it.

The air inlet is really sooty as were the injectors when I pulled them, is that normal and should I clean the air inlet manifold? The MAP sensor had a film of oily soot all over it so I wonder if that is maybe bad but I am clutching at straws now.
 
A mechanic with RR experience has told me it could be a bad Crank Position Sensor. This would explain bad idling and stalling wouldn't it? Is there a way to test the sensor?
 
Reinstalled the injectors, cleaned the air inlet, cleaned the MAP and cam position sensor and bolted every back together.

To my amazement when I started the engine the rough idle was gone:D. Been out twice on test and all feels good.

I have no idea what the cause was, diagnostics show same running values as when rough. Maybe the not very tight injector bolts, maybe dirty sensors or inlet manifold. Guess I'll never know but well happy, thanks to all who offered help and advise.

Just the MOt to pass tomorrow!
 
Reinstalled the injectors, cleaned the air inlet, cleaned the MAP and cam position sensor and bolted every back together.

To my amazement when I started the engine the rough idle was gone:D. Been out twice on test and all feels good.

I have no idea what the cause was, diagnostics show same running values as when rough. Maybe the not very tight injector bolts, maybe dirty sensors or inlet manifold. Guess I'll never know but well happy, thanks to all who offered help and advise.

Just the MOt to pass tomorrow!
Now that's a Fu king result mate. Well in there for biting the bullet :cool:
 

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