TDI 75 BHC with P2108 fault code Anti Shudder Valve problem

Sootywg

A2OC Donor
United-Kingdom
Just had EML come on, code identified is P2108, only change in behaviour is a shudder when switching off, so I guess ASV.
I have read what I can find on the forum but not much is said about the ASL most is about the EGR which on the BHC engine, I believe, are separate components. What has to come of to clean the offending part? Does the ASL come off first? I believe it is operated electrically so is it likely to be an electric fault rather than a mechanical fault
Inwill investigate tomorrow but any advance input would be appreciated

Thanks for any responses.
Geoff
 
Just put an answer on this thread for a similar issue

 
Thanks @audifan, I just saw your reply after I had deleted my comment!
I had a good read through that thread and I’ll take a look at the ASV tomorrow. Most of the thread seemed to be related to the ‘flap Motor error’ which I think is a different error code but it will be interesting to see what I find
 
With 'electronic' anti shudder valves I wonder if they modulate the butterfly to act as a swirl flap to optimise airflow during part load running or close it completely for the anti shudder function

Cheers Spike
 
Hi

i have had this issue in the past, checked unit, all clean and operating correctly, turned out to be the battery was a little low on voltage possibly due to short journeys, if you have a volt meter check your battery voltage
 
Hi

i have had this issue in the past, checked unit, all clean and operating correctly, turned out to be the battery was a little low on voltage possibly due to short journeys, if you have a volt meter check your battery voltage
The battery and charging I believe are all good but with recent reduction in use plus I was stuck in traffic before it first happened, it is certainly a possibility
 
The only common problem of the BHC engine. New VDO units are still available on ebay for around £170 last time I checked (pre-brexit).

If the flap is physically getting stuck then you will notice a drop in performance at some stages as the engine is starved of air.

It's most often an electrical gremlin and the best person to speak to would be @depronman because he has an electrical solution.
 
The only common problem of the BHC engine. New VDO units are still available on ebay for around £170 last time I checked (pre-brexit).

If the flap is physically getting stuck then you will notice a drop in performance at some stages as the engine is starved of air.

It's most often an electrical gremlin and the best person to speak to would be @depronman because he has an electrical solution.
The only symptom I became aware of after the EML came on was the juddering stop when the ignition was switched off, so it sounds like it is ticking partially open. Before I remove it to strip, should I not be checking on electrical components such as throttle position sensors and wiring? I am sure @timmus or @depronman could tell me what to look for and where to find the sensors.
Geoff
 
I would remove and clean the ASV
They tend to fill up with oil
Other failure is broken gears
If cleaning and checking gears doesn’t fix it then I’ve run the car with the valve connected but not in the airflow and observed the flap moving. It will partially close on low throttle settings to aid egr flow should open fully on acceleration and close fully when the engine is turned off
I have a ecu fix if the ASV is working correctly but the ecu complains about the ASV not reaching limits

Paul


Sent from my iPhone using Tapatalk
 
Well
Removed the ASV, not much oil in the body, even the EGR wasn’t as coked up as I expected.
opened up the ASL, no oil at all in the motor section…..but the big black gear is stripped!
I think I have found the cause of the error code.
Question is can the gears be replaced or is a case of a completely new assembly.
I can pick up a second hand one (‘cleaned and fully working’) or is that too much of a risk.
 

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You pays your money and takes your chance
From memory the new vdo ones are around the £200 mark if you can get a working second hand one for a lot less then it may be worth a punt
Yours is ok apart from the gears which is not a common issue with them so if the worst happened you should be able to make a good one out of the two
Drain screw going to post office now

Paul


Sent from my iPhone using Tapatalk
 
Well
Removed the ASV, not much oil in the body, even the EGR wasn’t as coked up as I expected.
opened up the ASL, no oil at all in the motor section…..but the big black gear is stripped!
I think I have found the cause of the error code.
Question is can the gears be replaced or is a case of a completely new assembly.
I can pick up a second hand one (‘cleaned and fully working’) or is that too much of a risk.

Audi A2 not listed, but suspect it will fit:


Do not be tempted to buy cheap Amazon ASV, I did and it didn't work........... money down the drain and lesson learned (again! ;-)).
 
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Thanks Menno. I had seen these but have no idea whether they are correct for our cars. Also being brass does that present any issues?
Do you have direct experience of these kits?
 
Thanks Menno. I had seen these but have no idea whether they are correct for our cars. Also being brass does that present any issues?
Do you have direct experience of these kits?
A while ago, with my first ATL the ASV was playing up and doing tricks with my check engine light.
So I bought an el cheapo brand spanking new Amazon ASV.
The cheap ASV was opening and closing but triggered EML again, guess software/hardware issues.

So I opened up the old ASV and found a worn/broken tooth, I managed to alter it somewhat to get it in working order again.
Before I had time to order the gears on Ebay I got hit by a woman ignoring a red traffic light, Exit ATL (write off), and did not require the gear repair kit anymore.
So, go ahead, order them give it a go and make an "how to"of it........

By the way: I opened up the Amazon ASV, to use the gears/sprockets of that one on my original, but unfortunely the mounting was different and incompatible. Pictures in the link below:

 
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I think I will try the repair kit. Always did like trying alternative ways to fix things.
The challenge I think is removing the ‘sector’ gear as to me it looks like it is moulded on to the metal plate.
As @A2Steve says this is a great club. Real Time support as I dismantle throttle body.
I may be calling on Steve for a replacement throttle body if I b****r up the current on. It would be a shame as everything else is clean and oil free. There was just a trace of oil around the spindle as one would expect.
Has anybody removed the butterfly spindle to check what the seals are like? The two screws that hold the butterfly to the spindle will slacken but I am not convinced that they are not ‘peened’ over so removing could shear them off and or damage the spindle. I am inclined not to do this as it may cause more damage but it might help in removing the moulded sector gear
 
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This video answers some of my questions, though I do not like the way he removes the spindle from the body!
 
I would not take the butterfly off the shaft. Diesels run on full air all the time so greater chance of the screws vibrating loose and being eaten by the engine. On your gear train is there too much missing or can you relocate the meshed gears again to allow full travel? Difficult to see exactly from your picture but suspect that gear is no longer useable. Plastic gear teeth are used as a designed failure point, if the butterfly is stuck then the gear teeth get sacrificed saving the motor or mechanism. Brass gears will last longer than plastic but you have immediately remove the protection element of the sacrificial plastic teeth. Would be more inclined to fit a clean and tested used ASV provided the mounting points and physical dimensions are the same as the A2 unit.
 
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