[Yph //]

Hello everyone. Ive just swapped out the engine in my newly bought 2008 T5 due to turbo failure on the old engine. Old engine was a BNZ, new is BPC.

Story is; some guy went to one of the best mechanic in town, and he told him the car had a turbo failure. I bought the car real cheap, and got a good price for a much lower milage BPC (174 hp) engine at the local scrapyard, so decided to swap engines instead. I was told the car was running just fine when they took it in (rear collision).

So, i swapped the engine, and i still get the P0299 underboost code. Local scrapper is really helpful, so i got to borrow shelf parts to try solve my problem.

Tried changing MAF, MAP, n75, n18. Egr is blocked, DPF is cleaed out (from the old BNZ engine).
Vnt actuator rod moves during startup, even tried changing the vacuum line from vnt to n75. Tried disconnecting exhaust, incase blocked, but no luck. No unnormal play or damage on the turbo at the new engine. Changed air and fuel filter also.

Power is always low, but sometimes it is restored, but only for a few seconds top. Live data says boost pressure is almost identical to atmospheric pressure (~1060millibar) and when power is restored it goes up to about ~2000millibar. Desired boost pressure is ~2500millibar at the same time.

So now im not really sure what the problem could be, or how to fix it. Anyone have a clue where i should check or what to fix? Also i started to check out the old turbo, and i could feel little play in it, and vnt pin is moving easy with fingertips, a little scrach noise is present, but i guess thats how metal to metal sounds. So starting to believe it may be something other than the turbo.

 

[Yph //]

Hello again. Here are some live data logging. Wierd thing is car is giving me boost pressure when im not asking for it. Can hear the turbo spool up when im going 80km/h, flat ground and on cruise control.

 

[Keithuk]

First posts normally go in introductions else you could get a free fix and we never see you again!!!

Forum Rules and Guidelines

What was that boost pressure scanned with?

Any problems search TDI Wiki as that covers write ups and forum posts.

You need to get your motor scanned (preferably with VAG-COM\VCDS) for any error codes logged in the ecu and post them, that will save a lot of guessing and check systems out.

Manufacturer: VW, Date(s) Used: 05/2007-05/2008, Model: Transporter, Engine Code: BNZ, 96Kw, 131PS, 2.5 Ltr, 5 Cyls, Remarks: Turbocharged Direct Injection Pumpe Düse (TDI-PD)

Manufacturer: VW, Date(s) Used: 06/2006-05/2007, Model: Transporter, Engine Code: BPC, 128Kw, 174PS, 2.5 Ltr, 5 Cyls, Remarks: Turbocharged Direct Injection Pumpe Düse (TDI-PD)

 

[Yph //]

Oh, im sorry. Did not see that. But i did purchase a VW, so you can count on me staying here.
Scanned with WoW by Wurth. Getting error P0299 Underboost. Will try scanning with VCDS.

 

[Keithuk]

As I've said: Any problems search TDI Wiki as that covers write ups and forum posts.

That's a common error code.

VAG Error Code: 16683/15343/15343/14914/11226/12896/7384/5171/5671/000665

EOBD II Error Code: P0299

Fault Location:
Boost Pressure Regulation - Control Range Not Reached/Low Boost

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.
Reduced Power Output.
Limp Mode.
Limp mode: What is it, what are the causes, and how to fix it for the Audi and VW TDI diesel turbo.

Hoses/Pipes incorrectly connected, disconnected or leaking.
Charger Pressure Control defective.
Turbocharger faulty.
Diverter Valve faulty.

Possible Solutions:
Check Hoses/Pipes to/between Components.
Check/Clean/Replace Charge Pressure Control.
Check Turbocharger.
Check Diverter Valve.

Special Notes:
If the Turbocharger is faulty due to mechanical/internal problems or the exhaust system is restricted (typically the Catalyst) this fault may be the end result.

Gasoline:
When found in 2.0l TFSI:
Check Boost Pressure Control Valve (N249) (Turbocharger Recirculating Valve) for cracked rubber diaphragm. A new/optimized Valve is available under Part # 06H-145-710-D (or newer).
Rest of World (RoW) vehicles see: Technical Product Information (TPI) 2016331 for details.
North American Region (NAR) vehicles see: Technical Service Bulletin (TSB) 01-07-70 or 2013392 for details.
When stored in conjunction with misfire codes and/or fuel trim faults see the notes associated with the following faults regarding Positive Crankcase Ventilation (PCV) failure: Crankcase Breather Valve
When found in Audi A4/S4/RS4/Cabriolet (8K): 2.0l (CAEB):
See Technical Product Information (TPI) 2031245/6 - turbocharger excessive waste-gate play.

Diesel:
When found in VW Golf/Jetta (1K): 2.0l CR-TDI (CBEA/CJAA):
Verify the mechanical part of the Exhaust Valve Control Module (J883) is not seized or binding.
When found in the 1.9 L TDI-PD (BLS):
Check vacuum supply from the vacuum reservoir located in the valve cover for leaks. Using a vacuum gauge, wiggle the valve cover and hose connections to check for a leak. The following photo was submitted from a customer working on a 2010 VW Caddy (2K chassis) with this vacuum reservoir problem.

As taken from my new Free EOBD II Error Codes software