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Rover 75 2.0 2004 - Intermittent cutting out - Fixed #

Posted by Geoff Taylor on April 19, 2012, 7:23 pm

Year of Manufacture *: 2004
Engine Size and Code *: 2.0 bmw diesel
( Optional ) ECU Type: bosch dde
( Optional ) Scanner Used: t4
( Optional) Fault Codes: none

Hi

This vehicle has been suffering since oct2011 we were told from intermittent cutting out some times at intervals up to weeks. The owner has been to numerous garages and because of the nature of fault no joy. Because we are xpart auto centre we were recommended (unfortunately).

when the fault occurs it stops abrubtly as though key turned off, no codes are logged it is turning out to be a thorn in our side,when looking at 16 live data parameters when cuts out the fuel high pressure isnt high enough to start engine.
my question is does the ecm have to receive a signal from crank angle sensor to initiate the fuel pressure regulator solenoid which controls the fuel pressure in fuel rail.

Geoff Taylor

Re: rover 75

Posted by Derek Smith <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3424' width='330' height='300' border=0 style='border:none;'> on April 19, 2012, 7:57 pm, in reply to "rover 75"
Derek Smith

Hi i had a bmw x5 with same kind of fault a few years back.It would just cut out and when you put a direct fuel feed on to pump it would start first time. I traced the fault to a inline fuel pump half way along the floor pan hidden under all the sheilds. I don't know if the rovers have one as well but worth a look.

Re: rover 75

Posted by Piotr Sokolowski <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1848' width='330' height='300' border=0 style='border:none;'> on April 19, 2012, 9:21 pm, in reply to "Re: rover 75"
Piotr Sokolowski

can you check ecu for water ingress. I did have one 75 long time age and it get me really mad.

Re: rover 75

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on April 19, 2012, 10:17 pm, in reply to "Re: rover 75"
Mark Carter

If the vehicle has high pressure issues you must check the low pressure system first.

What is the pressure in the low side?

What is the pressure differential across the filter?

Regards Mark

Modern cars, Its all wizardry and witchcraft

Re: rover 75

Posted by geoff taylor <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5467' width='330' height='300' border=0 style='border:none;'> on April 20, 2012, 6:32 pm, in reply to "Re: rover 75"
Geoff Taylor

low pressure side perfect, no water ingress in plenum chamber and only the fuel filter under bonnet which is ok.
but no one has answered my original question
geoff

Re: rover 75

Posted by Matt Booth <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3028' width='330' height='300' border=0 style='border:none;'> on April 20, 2012, 9:05 pm, in reply to "Re: rover 75"
Matthew Booth

Not sure about CKP signal for regulator but I doubt it. It is utilized from when the key is turned to position 2.

Are you aware of the in tank pump issues these suffer with? When the level gets to around 1/4 tank - which could explain the randomness. Over 1/4 the problem won't occur. The pump in the engine bay is problematic too.

Matt

Re: Rover 75 2.0 2004 - Intermittent cutting out #

Posted by James Eardley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3143' width='330' height='300' border=0 style='border:none;'> on April 20, 2012, 9:57 pm, in reply to "Rover 75 2.0 2004 - Intermittent cutting out #"
James Eardley

Hi Geoff

To test your theory you could interupt the crank signal and see if the ecu tries to drive the FPR or not.

I would think the rail pressure might still be regulated to start up pressures, with loss of crank signal but the ecu wouldn't fire the injectors(I may be wrong)

When the fuel pressure in the rail is not great enough for the vehicle to start can you see the ecu trying to drive the FPR to create more pressure?

What is the rail pressure when it wont start?

You should have a look at the supply pressure from the pump(s), including either side of the filter at different load conditions.

Also looking at supply pump current can give you answers somtimes.

hth

James

Re: Rover 75 2.0 2004 - Intermittent cutting out #

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on April 22, 2012, 11:21 pm, in reply to "Re: Rover 75 2.0 2004 - Intermittent cutting out #"
Mark Carter

>>> my question is does the ecm have to receive a signal from crank angle sensor to initiate the fuel pressure regulator solenoid which controls the fuel pressure in fuel rail.<<<

The PWM control for the DRV will be dependent on engine speed and engine load, referenced to a look up table inside the ECU, with the FPS completing the closed loop control circuit.

I would expect the DRV to be fed with a set PWM signal until the FPS signal is matched to the current engine speed/load map.

Then the PWM will move with the engine speed/load demand placed on it.

As others have said, scope the DRV with the Ignition on and the engine not running to confirm.

If the crank sensor was at fault I would expect a fault code because the ECU should "see" the cam signal without the crank and log a code somewhere around the P0335 range of codes.

If the rail pressure is very low when it cuts out perhaps you need to sit down and work out everything that could cause that. HTH

Regards Mark

Modern cars, Its all wizardry and witchcraft

Re: Rover 75 2.0 2004 - Intermittent cutting out #

Posted by geoff taylor <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5467' width='330' height='300' border=0 style='border:none;'> on April 28, 2012, 12:24 pm, in reply to "Re: Rover 75 2.0 2004 - Intermittent cutting out #"

UPDATE fixed
had ecm tested no fault found so back to the \drawing board/ started with dead basics ie battery connections onwards, at this stage still same symptoms eng start and run then cut dead.
at this stage had a stroke of good fortune or (divine intervntion?) after eng had stopped and was refusing to start my colleague was fiddling with the fuse box connections and lo and behold eng now fired up. on closer investigation we noticed on pressing down on the torx screw at the rh hand rear of a main connection which felt tight and then letting go the eng could be made to run and not run depending on pressure applied, we then removed fusebox and inspected fully and resecured a caged nut and rebuilt,the eng now kept running irrespective of pressure applied.
i assume this had temporally been not allowing a feed to supply side of pressure regulating valve plus other components which not allow valve to close and thus no fuel pressure to build up in fuel rail.
the customer has now had vehicle back 4 days and at moment i have all my fingers and toes crossed.
GEOFF.

Fixed #

Posted by geoff taylor on May 5, 2012, 3:36 pm, in reply to "Rover 75 2.0 2004 - Intermittent cutting out #"
Message modified by board administrator May 8, 2012, 2:24 pm

fixed
vehicle now been ok for 10 days
GEOFF.

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