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BMW 520D 2007 - Non start- no high fuel pressure #

Posted by Mark Lamont on May 7, 2018, 6:06 pm

Year of Manufacture *: 2007
Engine Size and Code *: 20 4 D 4
( Optional ) ECU Type: Bosch
( Optional ) Scanner Used: DecSS, Snap-on
( Optional) Fault Codes: None stored

Would appreciate some input on this before we push it out the door, I've probably missed something obvious. Car wasn't used and battery went flat, car recovered to me. No engine codes stored (more about that later). Nothing obvious in live data except no high fuel pressure. Good supply of good diesel at 5bar to HP pump, live data reads this too when cranking. Disconnecting IMV takes reading up to 120bar. I have access to a Delphi sealed rail kit, this showed no high pressure from pump, but over 1000bar when dummy actuator fitted so pump is ok. Good 12v supply to IMV and square wave (I'm trying to remember but about 50% duty cycle) so I ordered a new IMV, but old one has approx 5ohm (is this right?) and clicks when given 12v supply. New Bosch IMV is approx 10ohm but all data readings are identical to old IMV when fitted.
Running out of ideas, but I know it had a remap ages ago and I'm thinking that's masking faults, unplugging rail pressure sensor, IMV and rail control valve doesn't trigger a code. Any help would be appreciated

Re: BMW 520D Non start- no high fuel pressure

Posted by Steve Shaw <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3627' width='330' height='300' border=0 style='border:none;'> on May 7, 2018, 11:31 pm, in reply to "BMW 520D Non start- no high fuel pressure"
Steve Shaw

Hi Mark
does the imv have to be initialised?
i doubt whether dec ss will be much help on bmws'

Re: BMW 520D Non start- no high fuel pressure

Posted by Steve Harrison <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1363' width='330' height='300' border=0 style='border:none;'> on May 8, 2018, 8:35 am, in reply to "Re: BMW 520D Non start- no high fuel pressure"
Stephen Harrison

Mark

Have you done an injector return flow test?

Steve

Re: BMW 520D Non start- no high fuel pressure

Posted by Mark Lamont <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2555' width='330' height='300' border=0 style='border:none;'> on May 8, 2018, 9:52 am, in reply to "Re: BMW 520D Non start- no high fuel pressure"
Mark Lamont

The DEC has exactly the same functionality as my Snap-on which is fully updated. But I will borrow a launch today and see if that option is there, thanks Steve

Re: BMW 520D Non start- no high fuel pressure

Posted by Mark Lamont <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2555' width='330' height='300' border=0 style='border:none;'> on May 8, 2018, 2:34 pm, in reply to "Re: BMW 520D Non start- no high fuel pressure"

Very small amount off leak-off, just a small amount up the tubes with 20sec cranking. All injectors same amount. There is a reset procedure on Launch but hasn't made any difference

Re: BMW 520D Non start- no high fuel pressure

Posted by andy pethig <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3731' width='330' height='300' border=0 style='border:none;'> on May 10, 2018, 5:59 pm, in reply to "BMW 520D Non start- no high fuel pressure"
Andrew Pethig

have you concidered a stuck open injector or one that has lost its tip?

if the car has been burning oil it could have melted a injector tip/s

it should not be too hard to cap off each injector to see if pressure returns

andy

Re: BMW 520D Non start- no high fuel pressure

Posted by Mark Lamont <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2555' width='330' height='300' border=0 style='border:none;'> on May 11, 2018, 8:38 am, in reply to "Re: BMW 520D Non start- no high fuel pressure"
Mark Lamont

Thanks Andy, I have taken a reading from the back of the HP pump, I get 6 bar with ignition on and cranking whilst low pressure pump runs. With IMV disconnected I get 120bar cranking, and over 1000bar if IMV blanking plate fitted. The 6bar and 120bar figures are also seen in live data when everything is connected. So I either have a faulty new IMV or it's not being controlled correctly. I'll try and have another look today if time allows

Re: BMW 520D Non start- no high fuel pressure

Posted by Tony Ludford <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5539' width='330' height='300' border=0 style='border:none;'> on May 12, 2018, 11:46 am, in reply to "Re: BMW 520D Non start- no high fuel pressure"
Tony Ludford

Flat battery - jump started? Has the ecu been corrupted perhaps?
Have you got any way of re-flashing the ecu?

Re: BMW 520D Non start- no high fuel pressure

Posted by Mark Lamont <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2555' width='330' height='300' border=0 style='border:none;'> on May 12, 2018, 1:31 pm, in reply to "Re: BMW 520D Non start- no high fuel pressure"
Mark Lamont

Hi Tony yes that is a possibility, I'm told the battery was totally flat, and I dont't know the method used to attempt starting. It would be good to see it te ECU is able to operate any actuations, but it's been on 3 different scanners and they all only list the cooling fan...
I've only just started doing remapping, this car was done years ago but owner can't remember who by. I suppose I could try that if I could obtain an original file?

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