Diesel Diagnostics

Post a Response

VW Passat 2.0 TDi PD BKD 2007 - Judders excessively under load - Ongoing #

Posted by Eamonn Greene on March 9, 2015, 6:04 pm

Year of Manufacture *: 2007
Engine Size and Code *: BKD = 2.0D TDi PD
( Optional ) Scanner Used: VCDS
( Optional) Fault Codes: Glow Plugs (x4)

Hi All,
This Passat judders excessively when put under load usually between 2000 - 3000 rpm. You can still feel a slight juddering at very low revs (even when reversing at very slow speed).
The VW Dealership has fitted a new set of injectors (twice apparently) and a local garage has fitted a new DMF and a new fuel pump in the tank.The tandem pump pressures are okay.
The only thing I see wrong is that it appears to erratically miss some pre-injection pulses at random. I've enclosed a Pico capture when the vehicle was at its worst. I don't really know why this is happening and I would really appreciate all the help I can get at this stage. Thanks you in advance.

Re: VW PASSAT 2.0 PDi

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 9, 2015, 6:29 pm, in reply to "VW PASSAT 2.0 PDi"
Mark Carter

New harness fitted ?

Modern cars, Its all wizardry and witchcraft

Re: VW PASSAT 2.0 PDi

Posted by Eamonn Greene <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5362' width='330' height='300' border=0 style='border:none;'> on March 9, 2015, 7:17 pm, in reply to "VW PASSAT 2.0 PDi"

Sorry I was just unable to upload the original Pico files and I'll have to just use this jpg.

border=0>
Thanks for your reply Mark. Yes the loom is new as well.
Regards
Eamonn

Re: VW PASSAT 2.0 PDi

What is the injected quantity at idle both cold and hot, also what are the correction values cold and hot?

What is your torsion value reading?

Mark

Modern cars, Its all wizardry and witchcraft

Re: VW PASSAT 2.0 PDi

Sorry Mark,
I haven't got that info to hand at the moment.
I'll let you know soon

Re: VW PASSAT 2.0 PDi

Posted by Ian Slattery <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1196' width='330' height='300' border=0 style='border:none;'> on March 10, 2015, 9:28 am, in reply to "Re: VW PASSAT 2.0 PDi"
Ian Slattery

Hi Eamonn

I have seen a few worn inner drive joints on vw, worth checking.

Regards Ian.

Re: VW PASSAT 2.0 PDi

Posted by Neil Mellor <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2785' width='330' height='300' border=0 style='border:none;'> on March 10, 2015, 9:57 am, in reply to "Re: VW PASSAT 2.0 PDi"
Neil Mellor

Had a similiar problem with a Caddy same engine same year.
Diff bolts loose in gearbox causing judder under load.

Re: VW PASSAT 2.0 PDi

Hi Guys,
Thanks for your replies. I don't see any oil leaks from the gearbox but I'll check.

Sorry for taking so long to get back to you Mark.

Inject Quantity Correction figures:
Cold @ 8 Degrees
-1.16 - 0.98 - 1.49 - 1.22 Approx

Hots @ 85 Degrees
1.55 - 0.95 - 0.63 - 1.00 Approx

Injection Qnty at Cold Idle = 9.5 mg/str

Injection Qnty with juddering is as follows:
39 mg/str @ 40 kph under slight load
38 -42 mg/str at 60 kph (1800 approx) under acceleration
55 mg/str @ 60 kph (2200 rpm approx) under acceleration

Kind Regards to one and all
Eamonn

Re: VW PASSAT 2.0 PDi

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 10, 2015, 9:51 pm, in reply to "Re: VW PASSAT 2.0 PDi"
Mark Carter

>>> Sorry for taking so long to get back to you Mark. <<<

Don't worry about that, its not a race

Those figures look good, could you just give me the injected quantity hot at idle and the torsion value.

I have had the same as Neil with regard to the diff bolts, and would be worth serious thought after disproving the engine side of things.

Mark

Modern cars, Its all wizardry and witchcraft

Re: VW PASSAT 2.0 PDi

Posted by Jon Morgan <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on March 11, 2015, 7:29 am, in reply to "Re: VW PASSAT 2.0 PDi"
Jon Morgan

And,

Can you make sure the I.Q figures Marks asking for are at 80 - 85C on the coolant temp.

Re: VW PASSAT 2.0 PDi

Thanks guys for your help so far.

The Torsion value at hot Idle is -0.35 Mark.

The Fuel Qnty fluctuates between 3.3 - 4.7 mg/str @ 84 Degrees.

One other point which I forgot to mention.
No.1 is slightly down on compression compared to the other 3 cylinders.
On about the third crank revolution the compression on No.1 is 250 Lbs whereas as the compressions on the other three are approx 380 Lbs.

Would a bent con rod cause these sysmptoms with this car?

Kind Regards
Eamonn

Re: VW PASSAT 2.0 PDi

The cylinder with low compression is providing a 3rd less effort than the other 3 cylinders - this would have to set up some sort of harmonic vibration, with compression being the deciding factor for combustion, it may be less than a 3rd, but someone a little more technical can add to the theory there.

The torsion value is spot on, the I.Q wandering is an indication of the ECU attempting to stabilise the idle contribution across the 4 x cylinders.

The surprising aspect of the figures you've posted to me is:- the individual contribution on smooth running control for number 1 cylinder isn't bouncing on the stop.

I suspect this engine has either suffered a turbo failure & swallowed some oil.
Or..... when it had its 23H9 injector safety recall the head gallery emptied its fuel contents into No.1 cylinder as the injector was removed (why do technicians always start at number 1?.
The new injectors were fitted, the engine cranked & the inevitable hydraulic action occurred bending a rod?

There could be other scenarios, (camshaft.....) but whatever happened or is happening in number 1 cylinder requires investigating.

Re: VW PASSAT 2.0 PDi

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 12, 2015, 10:20 am, in reply to "Re: VW PASSAT 2.0 PDi"
Mark Carter

I can only second what Jon has said.

You must sort out the compression issuse before moving on

Mark

Modern cars, Its all wizardry and witchcraft

Re: VW PASSAT 2.0 PDi

Thanks guys for all your help.
It looks like the head needs to come off so.

Eamonn

Re: VW PASSAT 2.0 PDi

Posted by Kevin Apps <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on March 12, 2015, 4:59 pm, in reply to "Re: VW PASSAT 2.0 PDi"
Kevin Apps

Eamonn

Cylinder leakage test before you go removeing the head.

"The VW Dealership has fitted a new set of injectors (twice apparently)" The question of are they to blame needs answering BEFORE you get further involved.

Kev.

Re: VW PASSAT 2.0 PDi

Posted by Anthony Pickering <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3715' width='330' height='300' border=0 style='border:none;'> on March 12, 2015, 5:31 pm, in reply to "Re: VW PASSAT 2.0 PDi"
Anthony Pickering

Leakage test is a must and/or shoving a pressure transducer down the dipstick to look at bottom end pulses.

saves time taking a head off to find a bent rod.

Ongoing #

Posted by Eamonn Greene on April 19, 2015, 9:23 pm, in reply to "VW Passat 2.0 TDi PD BKD 2007 - Judders excessively under load #"
Edited by board administrator April 20, 2015, 12:01 pm

I would glady have posted a FIX for this vehicle but the truth is that the garage in questuin hasn't even looked at the car since.
They give a whole new meaning to the word 'SLOW'.
I will post a FIX for this when the job is completed possibly in 2016 knowing this useless lot.
Thanks for all your help guys.

« Back to index

[ Diesel Diagnostics ]