Desperate for help please

[dodge88]

Hi all,


2.0 TDI 57 passat estate - 95k full service history


I've owned this for a year now and have suffered a strange problem with it..


when idling the engine rocks as though its "catching temporarily" i.e when you catch your trousers on something it kind of pulls you back for a second but you keep going.


Not only this but the fumes from the exhaust will make your eyes water constantly and when idling outside the fuel gauge can be seen physically dropping after bout 5 minutes on idle.


My MPG is only around 32 / 34 mpg with 40 mile a day on Dual carriage way at 60 mph on cruise.


I own vag com and it has no fault codes at all, injector readings are all OK but my "torsion value is 2.9 (recommended is - to + 1.5 i dont know what that is :)


its just passed an Mot but the tester said it's got a bad problem as the fumes mixed with fact that the idle and fast test were the same readings is bizarre..


Any help on what live data / tests i can do through vag com to try and find where the fuelling issue (if it is one) is being caused?


It runs fine, no issues other than the lumpy idle and crap MPG. (responsive in low revs but seems to bottom out after about 2.25k


i did a re-gen last month to try and resolve which made no difference and have recently given it a good service with recommended fluids etc....


a Diesel specialist which is highly recommended near me want 90 + VAT to have a look and run some live tests, which i can do on vag com if someone can help point me in the right direction?


Thanks All for reading and i have searched the forum but cant find anything similar..


Thank you

[Rob69]

Your inlet cam timing is advanced, indicated by the +2.9 torsion value, I think this relates to 2.9 degrees of advancement, if you search looking for 'vw pd torsion values' or similar search you'll find info on what it means and how it can be adjusted relatively easily. It looks like when the cam belt was last changed, the locking tools were used but it was not finely set afterwards. Another problem could be the injector harness breaking down but that seems to lead to misfires and vcds would possibly pick that up as a code.

[DMitch16]

Torsion values differ from engine to engine and are not that relevant but you do need to learn how to use VCDS as you have it otherwise it just becomes a £200+ scanning tool essentially.

Shudder / vibration suggests either a misfire (the ECU ignores minor misfires so it could still happen on a code free engine) which may point to a fuelling / injector issue, a bad / stuck Dual Mass Flywheel or clutch issue or contamination of fluids (coolant / oil / diesel).

You haven't said what your engine code is (white sticker under boot carpet or small sticker on cam belt cover if still there).

[dodge88]

Hi Mitch - all i can find under the boot carpet is the letters 3c9?? its a 170bhp version.

Yes i agree its an expensive obd tool at the minute :)

Funny you mention Fly wheel as on start up the car sounds like a bag of spanners when starter is moving to fire?

Any pointers for VCDS to start looking at?

[dodge88]

thank you Rob - i will do some digging and see what i can find

[Crasher]

3C5 means Passat estate so it is probably a smudged 5 not a 9, with the 170PS engine it will be the BMR and these came with a DPF. I have had a lot of these in with foul smelling exhaust (even more than a diesel stinks anyway) and they had all had the DPF removed and a dodgy remap, re-installing the DPF and reflashing back to standard solves the problem.

[DMitch16]

They (the BMR) also occasionally came with cracks in the head as I found out in 2012. :aargh4:

And the dreaded oil pump drive key time bomb! :cussing:

He's not far from you Crasher!

[dodge88]

This may be the most silly response ever but i can see the DPF in the engine.

[dodge88]

oil pump drive key??

[DMitch16]

This may be the most silly response ever but i can see the DPF in the engine.

A DPF delete is done in short by opening the can and removing the filter element from inside then welding it back together so Mr MOT tester thinks nothing of it (it is technically illegal but has next to no policing). A remap and the appearance of some visible soot when you boot it but no more DPF. Becomes a DPT a Diesel Particulate Tube :yikes:

[DMitch16]

oil pump drive key??

Search the forum using the words oil pump drive failure.

There are 2 counter rotating weighted gear driven shafts in a frame bolted under the crank basically almost filling the oil pan. It is called a balancer unit and it counters the torsional forces acting on the crank to smooth engine vibration. One of the shafts is driven by a gear on the crank shaft through an intermediate cog and itself, using a gear half way down its own shaft drives the second shaft. In the end of the second shaft is a splined hole that VW decided to put a straight 77mm long hollow hexagonal bar into, to drive the oil pump which also has a hexagonal drive hole. The problem is threefold.
1. The amount of key drive depth is only 1.3cm into the balance shaft hole and being hollow the drive key is not the strongest or resistant to vibration.
2. The hole is not a match for the hexagonal key and the force exerted by shafts rotating at TWICE engine speed quite great.
3. The alignment / balance of the 6mm wide key inserted into the heavy second balance shaft was poor and over time vibration wore the two parts together rounding off both key and hole.
Ultimately somewhere along the line this unit loses the ability to rotate the oil pump and oil pressure vanishes. The car screams stop but as the warning is set for too low a pressure reading some damage may have already occurred and engine seizure imminent if you continue to drive the car. Parts affected already would be turbo, rocker bearings, cam shell bearings and any other parts dependent on sufficient oil flow and pressure.

95k is nearing the red zone - mine failed at 148k, others anywhere from the high tens of thousands upwards. I do think the amount of play between key and key hole and whether the shaft maintains a good balance with the key and pump holes makes a difference in the wear rate. Many other factors could affect this however. Distances, driving style, oil quality, service intervals etc. etc.

The KMB Direct fix is pretty much a permanent one. Fit modified shaft with hexagonal, deeper hole, longer solid, hard 100mm key bar (kit is around £215 plus tools and renewables) and then forget. Price if not DIY capable a few hundred more.

[dodge88]

well i had it looked at today - Garage claim that the emissions are at 1.16l/m...

They have said the DPF filter is in need of replacement and cannot find any other trace of issues relating to overfueling or anything similar..

[DMitch16]

They should read the Carbon Mass Index (Ash load). If over 45 grammes then the DPF is full.

[dodge88]

He claimed that the dpf wasn't communicating with there software - I will check with my vag com tonight see what it shows.

[DMitch16]

The DPF does not communicate with anything. The ECU records sensor inputs and is able to calculate the through flow of gases , soot saturation levels and resultant ash accumulation from regenerations. Connect up to VCDS, go to the Engine module, click on Measuring Blocks and select 068, 070 and 075 groups. These will tell you the soot saturation in percent from 0 to 45% active regen is demanded at 45% if passive regeneration has not been possible, 45 to 55% if active regenerations have been unsuccessful with DPF warning light on at 55%. Thereafter a forced regeneration is needed and the cause of the problem needs to be urgently rectified. And the Carbon Mass (collected Ash level).

[dodge88]

hi,

My vcds reading is attached - Any thoughts

[DMitch16]

hi,

My vcds reading is attached - Any thoughts

Carbon Mass at 47 grammes - DPF is pretty full probably needs cleaning or replacing.

[Gazwould]

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSbcdO2OPBmpVKiPLw8T2IT0RUUc7M5H DPHBgaVYO062qkpFj3pCw

[DMitch16]

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSbcdO2OPBmpVKiPLw8T2IT0RUUc7M5H DPHBgaVYO062qkpFj3pCw

Or illegally using a car without the filter element like the one in this picture. It is still not yet illegal to remove the DPF or element but it is to use a car that had one if it no longer has.

https://www.theguardian.com/environment/2016/apr/17/diesel-particulate-filter-removal-air-pollution-department-for-transport

[dodge88]

Hi,

before i I consider a new dpf. Can someone confirm the correct process for a forced regen using vag com please. At least if I try it I'll never say I didn't lol Thank you.

[Crasher]

Personally I think those that remove DPF's should be strung up by their balls!

[DMitch16]

Hi,

before i I consider a new dpf. Can someone confirm the correct process for a forced regen using vag com please. At least if I try it I'll never say I didn't lol Thank you.

Doesn't need doing as group 068 reads only a 4.6% soot accumulation presently. A forced regeneration will not removed accumulated ASH only burn SOOT into more ash. Your issue is most likely that the DPF is full and constantly regenerating at very short intervals. Back pressure will have increased and the car struggling to breath out. This extra pressure will most likely feed around to your EGR and back into the intake when the EGR is open almost a vicious circle. The engine will be labouring as it will be unable to perform as it should. A few hundred gets the unit cleaned, a couple of hundred more a refurbished / remanufactured (or supposedly new) unit but without labour included. VW will charge a grand upwards for a "genuine" unit and some for labour. Once done you'll have 95 to 150k miles before needing to do it again. The mileage at which the Carbon Mass has hit 45 grammes suggests the car has been used for a fair bit of town / short driving in the past as with proper mixed driving use the DPF capacity should not be reached for around 120 to 150k.

[Crasher]

A word of advice of new DPF's, avoid those from B&M as we have just been through a sketch with two on an A6 which we cured by having the damaged threads on the old one repaired and the internals cleaned by DPF Clean Team in Hinckley and then sent the two new unfit for purpose DPF's back to where they came from. These were also both their "premium" units!

[dodge88]

Ok, so new / refurbed dpf it is then.

Thank you you all for your help with this one and hopefully my car will stop trying to bleach everyone's eyes when idling :)

thank you.