BKD Turbo Removal

[Kalpesh]

Hi all,

Looking for a guide to help if anyone has one or can point me in the right direction

Thanks

Kalpesh

[jason_rmh]

I'll be doing this soon and found this guide looks useful:
http://www.audi-sport.net/vb/a3-s3-sportback-8p-chassis/149599-guide-how-remove-turbo-clean-sticky-vane-causes-overboost.html

Jas

[kevster996]

Ive just done this on my 2005 GT TDI 140 4motion and its a bit of a pig of a job due to access. I did manage to pull the turbo out of the top of the engine but I split the turbo off the DPF/exhaust to make it easier (danger of doing this is that bits may drop down from insdie the turbo if you're not careful).

I had already removed the EGR cooler and EGR as it dumped about 4 litres of coolant in, in a few miles (luckily had 5 litres in the boot as it had been leaking on long journeys). Not having the cooler in the way was a big bonus, its clearly been changed once already.

My clamp on the exhaust side was stuck on so that took a while to get freed off as so little space to get tools in there, I got a few swings at it by using extensions bars and a hammer from above and plenty of wd40. I dropped the O/S drive shaft so I could undo the bolts (5 I think) holding the turbo to the exhaust side casing and also get to the oil pipe bolts on the turbo.

The bolt holding the DPF on was a pain to get to and tight - its a 13mm and you can undo from above by getting a ratchet on the underside - easier than undoing the 3 bolts on the block.

I ordered a new vacuum actuator as mine didnt feel very smooth and its one more thing to iron out the limp mode issue. The fuel temp sensor was coming up as a fault - seems intermittent but cheap to replace and tidied up and checked the wiring to it as it was a bit messy.

The turbo itself wasnt as bad as I thought it would be and the VNT flaps were free - it probably got a bit of a clean when 4 litres of water got dumped through the engine! The EGR was squeaky clean when that came off - again prob from the cooler failure.

Fingers crossed getting it all back on once Ive got a few new parts in. I hope this fixes the intermittent limp mode as Im running out of ideas!

[Stupots]

@kevster996

Isn't yours a BKD engine too (same as mine) which doesn't have a DPF? Also, I had coolant dump issues on mine and it was a failed head/gasket. Early BKD engines are prone to porous heads, so I just replaced the engine all in one. Mine was blowing the coolant out of the expansion/top-up bottle, so may be a completely different issue.

I have to fit a turbo and change my clutch soon, so the less painless way (certainly on a 4motion) is taking the front off and having the engine out, but I know that's not an option for everyone (I just move the whole rad pack to one side, so no AC re-gas issues).

Good luck

Stu

[kevster996]

Wow I guess engine out does make it so much easier - I struggled but got there in the end. When I put the turbo and manifold back in I did it from the bottom as not enough spce with them both bolted together and didnt fancy splitting the turbo again. Ok to get it in from below as long as the driveshaft is disconnected and also I took off the actuator as just not enough space with it on.

Now its all back together i still get limp mode which is REAL frustrating! At least I know my turbo is good and Ive replaced the actuator so one less thing to rule out. Engine def sounds different, wastegate noisier (I assume its that - after accelerating and changing gear I hear a louder sucky noise between changes). Im not sure how well Ive clamped up the exhaust turbo clamp as you cant see easily how well this goes back together. I blew a few intercooler hoses but this was because I didnt put the clips on properly.

To answer your question yes mine is a BKD engine but I have a receipt for a head change so I think thats all good. My expansion bottle was fine - no real leaks on the outside so it was the cooler. I was assuming it does have a DPF - big lump/box thats attached just after where the exhaust bolts to the turbo and then drops down past the lower bulkhead into a section with mesh on the outside?

Im going to take it to a local vw specialist and get them to read the codes as CEL is no right now. Its fine from cold but after a few mins the limp mode kicks in. If I stop and restart it clears.

All I can think of now is to change all vacuum pipes, swap out the vacuum solenoid block or possibly MAF?   

Its a fun car but its hacking me off right now as Ive spent way too much time underneath it!

[kevster996]

@Stupots - how bad is your turbo? You could get away with a core replacement which is much cheaper than a whole turbo. Luckily mine looked ok and no end float or sideways float...

[Stupots]

My turbo is fine, but has a hybrid going on 

[kevster996]

Ah - nice - bit more power then... I had to refit the exhaust clamp as new one was blowing - I didnt fit it right the first time - they are a pita to see whats going on - sounds quieter now. Took it for a test drive and still get limp mode although not so quickly. I replaced a few vacuum lines so Im now thinking maybe faulty MAF or vacuum solenoid as it cant be much else...

[Stupots]

@kevster996 Hi, sorry I just read your post number 3 and can see a lot of info in there that I didn't answer...

The big lump/box straight after the clamp and before the flex section is in fact the Cat. I guess they put it there to make more room for the prop-shaft underneath the car on the 4motion.

I've picked up a new exhaust clamp, gasket, manifold gasket, manifold nuts and turbo oil return gasket for mine, so hopefully it will go on without any leaks. I'll get it mapped at Narco.

I see you fitted a new actuator... these can be really fussy on how they are adjusted on that thread... did you at least use your old one to set it in roughly the same position, maybe you're over boasting? Certainly with limp mode a VCDS scan can tell you a lot. If you're not sure if VCDS would be useful for you, you can try a cheap clone before buying a genuine one from Ross Tech. Even for simple things like resetting an airbag light it's definitely a must (in my opinion) for any VW owner.

Also I see you say "just did egr and cooler delete so a bit of weight saved there!" did you have the EGR mapped out? If not that will throw an ECL, though don't think it causes limp mode.

Try and keep the faith, there's not many TDI 4motions around and the MK5 is a great car to upgrade and tinker with. I've had a front end knock for 3 years and still not got around to fixing it.

Good luck

Stu

[kevster996]

Thx for your reply re my previous comments. Yeah they are pretty rare - great car when running right but its doing my head in right now, love the handling and its pretty quick for a diesel (had a quattro a4 and a6 before so stuck on 4wd now). I do need a VCDS - I took it to a guy I know and he cleared codes and we tried to map out the EGR but there was nowhere obvious - couldnt even override the settings where you normally go in and enter 33768 instead of 32768 so it doesnt trigger the warning?

Its had welding done for MOT but it failed on emissions - black smoke when revving it up. Ive put a new MAF on it (bosch one) as I disconnected it and drove it and it didnt go into limp after doing two hills, thought that would solve it but now it still goes into limp mode again. I did set the new actuator arm same as old one when I swapped it in.

Ive got it booked into local vw independent and they have all the kit and diagnostics so hope they can get to the bottom of it. All I can think that it is is a vacuum pipe somewhere or wiring for the fuel temp sensor or the vacuum solenoid (I dont have the N75) as Ive been through most other stuff. The mechanic today said he thinks its overboosting...

When you doing your turbo?

[Stupots]

The plan was to do the turbo this year when the weather warmed up, but it's getting colder again, so not sure it will get done this year now. I just need to book a few days off and get on with it (Clutch and timing belt at the same time). It's been in the loft for 3 years now.

I have other bits in my shed waiting to go on... Front and rear optical parking sensors, Highline reverse camera, Heated seats wiring loom... as well as some other bits and service parts that need doing.

This week I've tried to get some stuff done, but the interior is in bits at the mo as I'm wiring up the dashcam (that's been on the screen but not powered for 2 years), Passive TPMS, Air Quality Sensor, Passat (Mk7 style) Climatronic Controls and the single motor recirculation flap to go with it and a USB socket (where the ESP buttons etc go). I was going to write a guide on the flap swap, but it's been a right PITA so I don't think I'll bother.

Hopefully it will all work when I finish tomorrow...

[kevster996]

Blimey - thats a long list! Hope you get a chance to do some before it gets too cold - I dont have a garage only a car port so try not to do big jobs in the winter.

I had my car checked out at a local vw specialist - they confirmed that the turbo is fine and checked everything over - vacuum lines ok and the vacuum solenoid, actuator length etc. Its still overboosting with P0234 error code and they said that the air readings are way too high which is resulting in too much fuel being pumped through so MOT will still be a fail. The MAF is new and a Bosch one so they said thats fine.

As its been remapped before but I have no history I think the EGR delete has upset the ECU and whats been remapped. Im going to get it put back to standard but with a software EGR delete next week by a mobile specialist remapper. Hopefully that will sort the overboost and the limp mode/error code.

[kevster996]

Still no joy. Ive had the car mapped back to stock with an EGR delete - so basically paid someone to detune it and still not fixed the issue 

I cleaned up the boost pressure sensor and checked the earth leads and tightened up a couple of the intercooler pipes. Also checked the exhaust for leaks but that looks ok. Im really at a complete loss now as to whats causing the issue. Getting overboost and air flow readings too high so it pumps too much fuel in - I get some smoke when I rev it up so it wont pass the MOT...

confused.com

[kevster996]

New recon turbo on now and still get limp mode - same as before... Completely stumped now...

[Stupots]

Hi @kevster996 how frustrating... don't loose hope! The only thing I can think it could still be is a faulty Vacuum Solenoid Block (or vacuum pipe leak). Anyone close by that would be happy for you to swap that out to save you buying an unknown good 2nd hand part?

Not read back through the thread but have you had a VCDS scan yet?

Cheers

Stu