3.0 tdi throttle pause

[mhobson]

Had my A6 Allroad for over 4 years largely pleased with it but recently when you press the accelerator whether hard or soft at low or high speeds, there is an annoying pause before the engine pulls. Before you just had to touch the accelerator for an immediate response. VCDS shows no faults. Can there be ECU problems?

I look forward to constructive suggestions.

Thanks,
Michael

[AT.]

Before you just had to touch the accelerator for an immediate response. VCDS shows no faults. Can there be ECU problems?

It sounds like a turbo hole problem for me, maybe for some reason your charger has a slower response, or there could be a problem with the airflow.

I had a similar problem with my car. There was an air pipe in the engine area, which was almost full of soot, so my engine was even shut itself down, while there were no error codes in the MMI. After the cleaning of this pipe, I felt that the engine became stronger, so maybe this could be an answer for your problem too.

[mhobson]

Thank you for that, however the pause occurs before you would expect much turbo effect, there are no whistling noises which may suggest a vacuum leak and after the brief pause it accelerates a normal

[rowdy-999]

3.0 tdi rarely has turbo issues, just as ECU problems are again rare. Could be a throttle body problem, or maybe a throttle pedal postition sensor problem.

[mhobson]

3.0 tdi rarely has turbo issues, just as ECU problems are again rare. Could be a throttle body problem, or maybe a throttle pedal postition sensor problem.

Would those issues not have raised an engine fault on VCDS? Otherwise how would you be able to find the problem?

[rowdy-999]

Would those issues not have raised an engine fault on VCDS? Otherwise how would you be able to find the problem?

Not sure if this will help:

Manual throttle body (http://www.ebay.com/sch/i.html?_from=R40&_nkw=throttle+body&_sacat=6000) adaptation:

"The Throttle is "Drive By Wire" and adapts to your particular driving style. Do a TBA Throttle body (http://www.ebay.com/sch/i.html?_from=R40&_nkw=throttle+body&_sacat=6000) adaption).

1. Get in your car, it doesn't matter if you close the door or not.

2. Turn the key to the on position, the position just before the starter turns over.

3. Press the gas pedal to the floor with the key in the "on" position.

4. Hold the pedal to the floor for five seconds, then turn the key back to the "off" position(don't remove the key), then release the gas pedal.

5. Wait 2 mins. for a full alignment. During this time you may hear very faint noises and clicks. I
only heard one sitting in my car, if I got out and popped the hood I might hear more.

6. Drive the car as you always do.

Depending on your driving style, this may or may not be a big factor. I do a lot of city driving so
I noticed a big change after erasing my history. It is not hard to do this, just follow the
instructions - Key on, pedal down, 5 sec, key off pedal up, wait 2 minutes.

Keep the key in for the entire thing.

[AT.]

Thank you for that, however the pause occurs before you would expect much turbo effect, there are no whistling noises which may suggest a vacuum leak and after the brief pause it accelerates a normal

Honestly, I mean quite the opposite situation, maybe some air pipe is so clogged, that the turbo can't get enough air to spin up, and that may cause a delay. Your problem sounds similar to me, because there was no noise, or error codes in my case either.

[mhobson]

Honestly, I mean quite the opposite situation, maybe some air pipe is so clogged, that the turbo can't get enough air to spin up, and that may cause a delay. Your problem sounds similar to me, because there was no noise, or error codes in my case either.

I know what you mean, but I live in rural France, rarely travel in towns and the car has a DPF which I know is a pain and and gets blocked in city driving but particle readings are always low so I feel that the car runs quite clean, I normally get just above or below 40 mpg, and after the short pause on the throttle the car pulls as well as ever, the boost pipe is steel and quite big 10 or 12 mm so I expect it would nedd quite a lot of gunk to block it. The carvuses very little oil, I never have to top it up between oil changes.

[C6Allroad]

Symptomatic of a sticky EGR valve that is not closing fast enough.

[MarkTM]

Maybe worth looking at this thread as well

Good preventative maintenance and I noticed my throttle response improved afterwards

TB Cleaning Photos (http://www.vwaudiforum.co.uk/forum/showthread.php/161864-TB-Cleaning-Photos)

Once I've bought my new manifolds I'll be getting an EGR delete and have the EGR mapped out...which weirdly costs the same as a full remap!?

[AT.]

TB Cleaning Photos (http://www.vwaudiforum.co.uk/forum/showthread.php/161864-TB-Cleaning-Photos)

"All looks pretty clean ? In fact the only very clogged part was the "nostrils" inside the big pipe, which were completely blocked - pouring something down the small pipe didn't appear at the nostrils at all"

Thank you for this thread, I think, that's the pipe I talked about earlier.

[mhobson]

Symptomatic of a sticky EGR valve that is not closing fast enough.

Would not a sticky EGR generate a fault code?

[C6Allroad]

No idea - just going on the symptoms. A stuck open/closed EGR would but a sticky one that is slow to actuate..........?

[mhobson]

Hello, The problem has continued and if anything has got worse. Today I took the car to my local VW garage, they say that I need a new turbo, the problem they say is with the actuated progressive vanes behind the turbo proper, they are not working properly. They say that I must buy a turbo unit complete and it has to be set up by very specific electronic equipment only available from Audi, which as a VW dealer they have access to. I would appreciate advice as I have seen new turbo advertised for less thsn €1000,

thanks, Michael

[MarkTM]

Michael,

Are you running a kosher VCDS, or a cloned or lite variant?

As anything like the symptoms you're experiencing will show as a fault.

Just some other things to check, air filter/oil filter/fuel filter, when were these last changed?

[mhobson]

I did reply yesterday but it does not appear to have been posted. When the vcds 12.12 has been used before, it has always shown stored faults if they were there. There are no stored faults at the moment. I gave the car an oil change last week with all filters, oil, air, diesel and cabin.

[MarkTM]

I did reply yesterday but it does not appear to have been posted. When the vcds 12.12 has been used before, it has always shown stored faults if they were there. There are no stored faults at the moment. I gave the car an oil change last week with all filters, oil, air, diesel and cabin.

VCDS is on version 16.8.0, so the answer is no you've not used an up-to-date or kosher one :(

[Atlas]

If it is sticky turbo vanes, then you could try Mr. Muscle treatment before dropping big bucks for new turbo. Run Google with "Mr. Muscle turbo clean" and you will find plenty of instructions and discussions about it. I haven't done it nor everybody approves it but generally it seems to work.

[mhobson]

Hello, Yes I had a look at that and it seems quite interesting but I have reservations about possible damage to other parts of the engine which might ensue after using such powerful and possibly corrosive detergents, had I been a sharp geezer after moving the car on quickly I may have tried it but I hope to keep the car as long as possible.

I have found a new Borg Warner KKK turbo for a price less than half the price charged by Audi but the issue seems to be programming the actuator, when the turbo is fitted I have been told that the actuator has to be programmed before the turbo will work correctly but the electronic equipment necessary to do that is held only by Audi, and unless they supply the turbo they will not progran the actuator, I wonder is there no way around this issue? It seems a real con, surely there must be some way around it?

[B5NUT]

Think you would need to be nuts to put a caustic solution like mr muscle into your turbo, and then all of the mr muscle & some of the dirt that may have been removed goes straight into your DPF. I would avoid at all costs.

I've just replaced my turbo, as it had done 200K miles and the engine felt a bit down on power, so I just had my turbo refurbished and a new actuator was fitted by the company. If your buying a turbo with actuator already fitted then you don't need an "Audi programming" as it will have already been done and is stored on the actuator. I replaced my turbo at home and the car has been been running file and the power appears to be back to normal.

Here are a few pics and info when I replaced my turbo.

Remove the air inlet pipe & oil feed pipe to the turbo before starting. First the 3 bolts holding the exhaust side was removed
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160504_16_09_56_Rich%20Medium_zps2bd1tyom.jpg
Then the 3 bolts to the exhaust manifold (http://shop.ebay.co.uk/?_nkw=exhaust+manifold).
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160504_16_10_07_Rich%20Medium_zpslxierdgf.jpg
Then the two bolts holding the turbo mount to the engine, one is just below the exposed turbo to exhaust stud (http://shop.ebay.co.uk/?_nkw=exhaust+stud) on the photo and the other is to the left of the picture just behind the EGR cooler.
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160504_16_10_14_Rich%20Medium_zpsnszwqddd.jpg
Next is the bolt holding the oil return pipe to the turbo. Is the bolt in the middle of the image with green mark on it. Once that bolt is removed you can pull the pipe away from the turbo, however it will be stuck in there and takes a lot of effort to remove.
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160510_19_10_40_Rich%20Medium_zpsarzmdjcz.jpg
The final bolt which not not difficult to get to but easy missed is the lower bolt holding the turbo bracket to the engine. It is just visible in the centre of the image to the left of the little pool of oil on the turbo. Took me a while to find this last bolt as it's not obvious in elsawin.
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160504_18_54_38_Rich%20Medium_zpsnc2lvoya.jpg

So a few days later the refurbished turbo came back
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160508_15_31_38_Rich%20Medium_zpsvixhrf4t.jpg
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160508_15_31_44_Rich%20Medium_zpsgozvlwtm.jpg
http://i1339.photobucket.com/albums/o708/exchange56/engine4/WP_20160508_15_32_01_Rich%20Medium_zpsjrzkjaah.jpg
Fitting it is just the reverse of removal, just make sure the oil return goes back in, and make sure you fit a new o-ring, and all new turbo gaskets.

[Atlas]

Well, I might be a bit nuts as I have been thinking to do the Mr. Muscle treatment :o. I have specially looked for info why not to do it but so far I haven't found such. It is very alkaline (sodium hydroxide) and caustic to aluminium so you have to be careful with cylinder head and get the stuff to the right place but other metals and ceramics can tolerate it just fine. DPF has been my main concern as it will get heavy load of carbon deposits. It might have to do couple extra regenerations but I don't see why it couldn't burn them off and at the same time vaporize off the remains of Mr. Muscle.

Sorry for going off topic and excellent writing from turbo change B5NUT and I might need those instructions after my possible trial :Blush2:.

[Rob69]

I haven't and wouldn't do a 'Mr Muscle' , I think there's a good chance you end up damaging the piston ring type shaft oil seal at the back of the turbine wheel and end up filling the exhaust / DPF / etc with oil and that will cost you more to fix than a recon turbo would have and you'd still have to replace the turbo any way. Not convinced your DPF will handle a slug of sodium hydroxide / carbon crud either. The VNT mechanism that sticks is behind the turbine wheel backplate and I'm not sure how effectively the carbon can get out of there anyway with Mr Muscle without physically removing it.
I'm sure there are those here that will testify Mr Muscle worked fine and no problems but a big risk IMO.

[kanecullen89]

Think you would need to be nuts to put a caustic solution like mr muscle into your turbo, and then all of the mr muscle & some of the dirt that may have been removed goes straight into your DPF. I would avoid at all costs.

I've just replaced my turbo, as it had done 200K miles and the engine felt a bit down on power, so I just had my turbo refurbished and a new actuator was fitted by the company. If your buying a turbo with actuator already fitted then you don't need an "Audi programming" as it will have already been done and is stored on the actuator. I replaced my turbo at home and the car has been been running file and the power appears to be back to normal.

So yours had 200k on the original turbo on a 3.0 tdi? That's very impressive. I'd heard that that 3.0 tdi had a good quality strong turbo but didn't know they would last that long!


Sent from my iPhone using Tapatalk

[B5NUT]

Yes 200K miles, the engine was down a little on power and the company said the actuator was not in the best of conditions when they stripped it down.

[mhobson]

Tank you for that B5Nut, however when I contacted the vendor in Germany who are selling a brand new Borg Warner KKK turbo for around €719, they advised that the actuator will have to be programmed by an Audi garage before it will work correctly, which is what my local VW garage said, but they will only do it when it is them who supply the turbo which at €1800 for the same unit in my view is plain extortion. There seems to be no play on the main turbo shaft so the problem is likely to be with either the actuator motor or the boost vanes but VW Audi will not replace parts they will only replace the complete turbo. It seems that it is people like me who have owned Audis since 1979 are the ones having to foot the bill for the billions being given to the US in compensation to the fuel consumption fiasco. In the short term I plan on using fuel additive which may clean the vanes if they are a bit clogged, but apart from that I am not sure what I will do.

[B5NUT]

Give these guy's a ring, they fully program the turbo, and there is a label on the turbo stating the actuator must not be removed as it's programmed for the turbo it's mounted on.

Remanufactured Turbochargers - new,repairs, (http://www.turbocharger-solutions.co.uk/)

Price wise you looking at around £500 if you send back your old unit. Understand there will be shipping costs, but with the £ to Euro exchange rate at the moment it's not a bad price. I've had my turbo in my car for a couple of months now and the car drives fine, no fault codes and no VCDS coding was required.

[mhobson]

I have sent them an email, did they supply new gaskets or did you have to buy them separately?

[B5NUT]

They did supply some gaskets but others I just from Audi

[mhobson]

I have had a couple of emails from Neil Leighton at turbo solutions in Darlington who seems to feel that if a turbo is supplied complete it does not need programming, it should set itself when you turn on the ignition which is contrary to other advice I have received. It seems I know less about turbos than just about everyone else. I wonder if the same Borg-Warner KKK turbo is used on a number of different vehicles, the boost level has to be adjusted accordingly so B5NUT when your turbo was sent for refurbishment, the actuator was already set at the correct level, but if I was to buy a new one it would have to be set to give the correct boost for 233 bhp?

[B5NUT]

The actuator was replace as the old was in a poor state (internals) the shaft had some scoring so that was replace the the main body was was shot blasted and cleaned up, cannot remember about the other internals but I think some were replaced.

As I said there was a sticker on the turbo (wish I'd got a pic now) stating the actuator had been programmed for the turbo and it should not be removed, remember they have to be programmed as turbo solution fully test the turbo before it is returned to the customer. All I can say is the turbo i received back was plug and play.

There was also a member on another forum I go on who had this turbo fail as had to be a complete replacement, he also replaced that at home with no special tools or programming. Have sent you a PM with that thread, as I don't think the mods like linking to other VW/Audi forums.

[mhobson]

I am still very confused about the actuator programming. The VW garage who I hope to fit the turbo say that it must be programmed once fitted. A company in Germany selling brand new turbos say that it has to be programmed before use but companies in the UK selling reconditioned turbos with new actuators say that the actuator is programmed automatically by the ECU upon initial connection and they are virtually plug and play, can someone tell me definitively what is the case. The VW garage obviously want to sell a new turbo, and although maybe prepared to fit a recon unit, they may just be trying to put me off. Problem is I don't have €2200 spare and the car is a pain to drive.

[mhobson]

So I have spent a s..tload of money on this problem, car went away to genuine VW garage, they replaced the turbo and also for some reason the air mass meter for which there had been no fault codes and I am sure was unnecessary, the car has come back and.......guess what? The problem is exactly the same as before, throttle to the floor in the appropriate gear, appropriate revs and you have to wait sometomes several seconds before there is any response. My wife's A4, I know a lighter car, but with the exact same ASB engine, the throttle response is immediate. There seems to be another issue as well, when after a run slowing down for a junction for example there is a smell of engine fumes coming through the air con. The rubber bonnet seal between the engine and A/C seems sound.

[lynalldiscovery]

I havent read the entire thread so this may have been asked already, have you checked auto gearbox oil level?

[mhobson]

Thanks, but the car has a manual box

[pawelzaucha88]

So you ended up replacing fine turbo? If the problem is back can you get your money back for a wrong diagnosis on the part of VW garage?

[mhobson]

Could this issue be because of a faulty throttle body or throttle position sensor, and if it was should there not be a fault code. On a long drive today the normally smooth cruise control seemed a bit lumpy, the engine seemed to be delaying changing power up and down hills, I don't seem to have any other symptoms, how could I make sure if it was. Engine not swiftly responding to ECU.

[zit501]

Could this issue be because of a faulty throttle body or throttle position sensor, and if it was should there not be a fault code. On a long drive today the normally smooth cruise control seemed a bit lumpy, the engine seemed to be delaying changing power up and down hills, I don't seem to have any other symptoms, how could I make sure if it was. Engine not swiftly responding to ECU.

Hey there,

Sorry to drag up an old thread, but I see it wasn't resolved in the end and wasn't too long ago. Did you ever find the cause and fix the issue?

I'm experiencing something similar on my 3.0TDi BMK engine. It's intermittent, in that some days it does it, some days it doesn't. It drives fine at part throttle, but when I go to medium or floor it, it's like it's holding back (almost like weak or poor spark on a petrol).
I am getting no codes on either the engine or transmission.

I have had turbo actutaor issues before, and it's been replaced. I would always get codes for that, about the regulation of the turbo not being met. Like I said, no codes this time.

It seems like an input signal sensor more than an output from the ECU. It's like the ECU is getting erroneous signals. If I were to guess, I would go for air flow meter. I had similar issues with my MAF on my previous 1.9TDi. The ECU wouldn't throw a code since it couldn't see the fault, just that it was getting junk data from the MAF. I guess it could also be a MAP sensor, or even cam or crank, but generally those I think the ECU can tell are erroneous.

[mhobson]

The issues on my car have improved, more by luck than judgement. Naïvely I thought that if I took my car to main dealer garage, they would be able to solve the issue, but these are complicated engines and faults are difficult to determine even by specialists. Not only did the garage replace the turbo, actuator, and air mass meter which had been showing no faults, but when they replaced the engine undertray instead of using the VW Audi tray clips when putting the tray back on, they used pop rivets with washers, so that when I changed my suspension arms and needed to remove the tray, I had to drill the rivets out, which wrecked all the female clips and I have still not located replacements for the two female clips that sit inside the steel rear crossmember, so the rear is temporarily held by cable ties. After all that, the car ran no better than before, and I had a big bill. What changed was that over the years I have noticed white smoke coming from the exhaust when stuck in traffic, which living here is very rare. Recently after following several VWAF posts I saw reference to this fault caused by worn diesel injectors. For a 2006 car I was not prepared for the ridiculous bill of taking it to a main dealer garage nor fitting new injectors. From ebay germany I sourced a set of reconditioned injectors, which cost €399 delivered, I had to buy an injector puller set for about €84 and I changed the injectors myself with the help of someone with a computer to code them. The improvement in performance was frankly shocking, it has never gone so well, gives a kick in the back which it never had but there is still a little bit of turbo lag. It also uses less fuel. It solved another problem which has cursed the car for some time, engine fumes coming into the cabin. I suspect the injectors were overfuelling the cylinders with some excess fuel going into the sump, I did notice the oil level rising over time, and the diesel fumes were vented when I slowed down to a junction, maybe from the oil filler, there was oil vapour residue around it. This problem has since not reappeared. There have never been fault codes for air mass meter nor injectors on this car since I bought it in 2011.

[zit501]

Hey,

Thanks for the reply. That's a pity you had to be subjected to the expense of a new turbo, actuator and MAF, all for nothing! Typical dealer mechanics these days. (actually a lot of mechanics in general).

I've replaced my injectors already, due to them dribbling like everyone's end up doing. So I don't think it's those.

My problem is very intermittent. I can't recall now if yours was all the time or not. When it becomes more regular I'm going to have to start logging the various sensor signals whilst driving. I was doing this on the way to work yesterday, and as usual the problem was completely gone from the day before.