Diesel Diagnostics

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VW Golf V 2.0 BKD 2004 - Rough Idle & misfire - Unresolved #

Posted by Jon Morgan on June 27, 2011, 7:09 pm

Year of Manufacture *: 2004
Engine Size and Code *: 2.0 BKD solenoid unit injectors
( Optional ) ECU Type: Bosch EDC
( Optional ) Scanner Used: Autologic
( Optional) Fault Codes: No DTC's logged

Hi chaps, after some help / advice with this machine.

Symptoms - this engine starts ok & after 30 seconds runs continuously rough at idle - in the same way as if the EGR Valve was sticking open.
If left running for 20 mins or so, it smooths out somewhat but never gets to a satisfactory, smooth tickover.
The correction values in MVB 13 have gone to extremes on cylinder 1 & to some degree on 4 when the tickover is at it's best.
It suffers, bucking / multi cylinder misfire at idle, but smooths out & runs fine at higher revs.

Tests so far;

Scanned fault memories - no DTC's logged

New DMF & clutch fitted due to clanking at idle / clutch judder & misfire. Not clanking, juddering any more since new DMF & Clutch - but still has rough idle.

Fuel pressure at idle - low pressure = 0.5 bar (scoped & looks good) high pressure = 3.5 bar at idle, over 10 bar when revved or return line clamped.

Diesel looks & smells of diesel - not black, fuel filter inspected & changed

Coolant temp sender scoped - no glitches from CTS.

MAF scoped - 2V at idle, 4.5V at WOT.

Injectors scoped - look the same as a good BKD we had in today.

Head harness inspected, looks okay, all 4x injectors give a reading of 0.2 ohms when resistance tested via pins in the head multiplug.

Smooth running correction values; when running as good as it ever runs at idle, (MVB 13)

Cyl.1 minus 3.1 mg/h
Cyl.2 0.68
Cyl.3 0.94
Cyl.4 1.34

Smooth running correction when idle is as rough as it gets

Cyl.1 minus 1.15 mg/h
Cyl.2 0.26
Cyl.3 0.26
Cyl.4 0.61

Injectors removed & switched 1 >3 & 4 > 2, no difference to smooth running correction, i.e still compensating heavily on No.1 & 4

Carried out relative compression test via scope, - highest peak 307A, lowest peak 304A.
Reflashed engine ECU to latest software version - no change.
Removed EGR & ran engine without it due to the similarity of symptoms to a stuck EGR - no change

No previous history on this car, new to us & to customer.

Getting a touch flummoxed with it at the moment,
any ideas?

The only saving grace is Frank Massey is having the same trouble with one in Aftermarket magazine.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Piotr Sokolowski <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1848' width='330' height='300' border=0 style='border:none;'> on June 27, 2011, 8:59 pm, in reply to "VW / Golf 5 Diesel, Rough Idle / misfire"

camshafts lobes? Tappets?Just some ideas, maybe compression.If there is no fault codes could be mechanical issue.

Link: www.pandpauto.eu

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on June 27, 2011, 10:31 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Jonathan Morgan

Cheers Peter,
I have just had a push in the right direction with my scoping technique.

I had the scope set up badly & missed the signal dropouts on the injector harness - I have now been educated by a scope jockey & will be investigating further tomorrow.

Jon

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by lee <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1074' width='330' height='300' border=0 style='border:none;'> on July 7, 2011, 3:10 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Lee Pritchard

hi,what scope settings are you using?just for curiosity?

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by John Ritchie <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2638' width='330' height='300' border=0 style='border:none;'> on July 7, 2011, 8:58 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

HI Jon ,

A bit of a long shot but seeing there is no history with this car then maybe it has had injectors fitted & not setup correctly ?.
I would go with what Sean has mentioned (check valve timing .
Also on live data what boost is it running at?

HTH
John

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on July 7, 2011, 10:44 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

Thanks for the reply John,
At idle - Charge Air Pressure is at 989mbar.
Valve timing checked now & setup correctly.

Injectors have been removed, exchanged places & setup.

This only runs rough on it's warm up phase, after that it's as smooth as most BKD 2.0's.

Cheers,
Jon.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Mark Carter on July 8, 2011, 6:20 am, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Message modified by board administrator July 8, 2011, 1:58 pm

Hi John,

I bad re-map ?

Have you tried a re-flash ?

Regards Mark.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on July 8, 2011, 7:04 am, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Jonathan Morgan

Hi Mark,
PCM has been reflashed with latest VAG update,
cheers

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Glen Strachan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat1463' width='330' height='300' border=0 style='border:none;'> on July 14, 2011, 5:22 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

I would be taking a look at the manifold flaps next

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Richard Mackereth <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1076' width='330' height='300' border=0 style='border:none;'> on July 15, 2011, 9:55 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Richard Mackereth

Have you checked amps draw on all the injectors?
We have a amps clamp the fits on our scope that is great for showing up dud injectors or wiring in the head.

Have you set up the injectors, info is on bosch kts if you have one.

HTH
Richard

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on July 17, 2011, 8:13 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Jonathan Morgan

Scoped this one to death - Injectors, all 4x shut down for 62ms while the engine is bucking / misfiring.
The ECU is seeing something it doesn't like & shutting it's injectors off then back on.

In MVB 13 the value for all 4 x injectors switches to 128 - (this is the same value as over run shut off displays while driving).

Tried swapping injectors between cylinders, swapping ECU with a known good, disconnecting cam & crank independently to rule out correlation issue between sensors, scoped ECU feeds / earths / APP 1&2 / cam & crank / CTS / ran engine with V157 manifold flap & EGR removed to rule out air starvation / disconnected alternator to rule out interference / disconnected ABS ECU to make sure it wasn't broadcasting b*llsh*t into the bus etc......

Running out of ideas with it now

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Phil Kingdon <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1433' width='330' height='300' border=0 style='border:none;'> on July 18, 2011, 7:24 am, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Phil Kingdon

Oil grade?
Phrom fill.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Fiachra Purcell <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3006' width='330' height='300' border=0 style='border:none;'> on July 18, 2011, 10:13 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Fiachra Purcell

Did you try disconnecting the injectors one by one?
I know it sounds unlikely but your symptoms are similar to the one I had.
I also had injectors dropping out randomly. It was like the ECU was getting confused and dropping injectors to try to regain control of smooth running. It was not until I disconnected the injectors one by one that I found the Problem.
Speak to Jack in Autologic VAG. I went through it with him.
HTH
Fiachra.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Dave Hill <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2783' width='330' height='300' border=0 style='border:none;'> on July 19, 2011, 1:06 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

Hi Jon

I noticed that you perofrmed a relative compression test with Pico, but I would want to follow this up with a more acurate test, to confirm mechanical integrity.

i have had a few cases where the Pico starter motor current amp ramps appeared to be equal, only to later find a bent con rod.

my examples were on Ford TDCI's, but in both cases, I had a very slight "misfire" from cold start, that was not apparent when warm.

I also had a misfire DTC last winter on a Passat 2.0ltr TDI, which would only manifest itself on the coldest morning. This was the result of a failed glow plug.

Probably no help whatsoever, but I thought it worth a mention.

Cheers

Dave

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on July 19, 2011, 7:32 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

Update on this, ours has temporarily left us due to the owner needing to gat back to his Army base 150 miles away. We'll see it again next time he can spare it.
There is a garage in Essex with exactly the same issue, he has been working on his for a couple of weeks now & we have compared notes & between us tried different approaches.
Anyhow, this morning on the advice of Autologic, he slightly advanced the exhaust cam to a point where he was no longer able to insert the locking pin. Locked it off & it ran perfectly through the warm up phase. This info was gleaned by AL off an American website from a tech suffering the same issue on an early BKD engine.
Thus far it appears to have worked - when I get mine back, I'll give it a try & if successful post it as a fix - if not Fiachra, Dave, Phil - I'll work through some more tests.

Cheers so far,
Jon.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Fiachra Purcell <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3006' width='330' height='300' border=0 style='border:none;'> on July 21, 2011, 8:56 am, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Fiachra Purcell

When you get it back and advance the timing can you check MVB 4,4 to see how far advanced it had to go.
Thanks.
Fiachra.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on July 21, 2011, 5:01 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Jonathan Morgan

Will do, if that doesn't work - I'll start knocking the injectors out individually, I'll let you know either way Fiachra.

Cheers,
Jon.

Re: VW / Golf 5 Diesel, Rough Idle / misfire

Posted by Glen Strachan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat1463' width='330' height='300' border=0 style='border:none;'> on October 20, 2012, 11:23 am, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"

was there a fix here ? What did the MVB 4 get set to ?

Unresolved #

Posted by Jon Morgan on January 28, 2013, 8:25 pm, in reply to "Re: VW / Golf 5 Diesel, Rough Idle / misfire"
Message modified by board administrator January 29, 2013, 3:16 pm

Unfortunately we never saw this vehicle again, I only hope the squaddie who owns it is still alive & gave up on us - he was off on a tour to Afghanistan.

I have it on good authority that advancing the exhaust cam slightly, sorts out the misifire & evens out the lumpy idle suffered by so many BKD engines.

(But don't blame me if you maladjust it & it all goes Pete Tongue)

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