Loss of power / limp mode - Audi A4 2.0tdi 170BHP

[Bethj]

Hi there

I've just been reading through the forum and thought that perhaps someone might be able to shed som light on a recent problem I've had with my 07 A4 170 - the most recent of a long line of problems I've had to be honest. Ever since I've owned the car the glow plug light has flashed intermittently, with the car losing power and going into limp mode. By switching the ignition off and back on again this seemed to clear the problem until the next time it happened (only about once every few months or so). To be honest the full 170 hp has never seemed to be there right from the very beginning. Recently, this started happening a lot more frequently until the engine management light came on and will not go off. I've taken it in to an independent garage I've been recommended to. I spoke to the chap today - he's checked the inlet manifold and all seems to be OK and also the turbo seems OK too but the fault code he is getting is P0299. He is now going to look at the wastegate as a potential source of the problem. Is there anyone else who has experienced similar problems and what was the fix? I know that I'm hoping for a bit much to get a simple fix to this but I am now losing patience with this car :aargh4:

Any information / suggestions for what to check for would be greatfully received.

Many thanks

Beth

[Crasher]

16683 (P0299) - Boost Pressure Regulation: Control Range Not Reached (underboost)

Possible Symptoms
Reduced Power Output
Limp Mode

Possible Causes
Hoses/Pipes incorrect 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


This is becoming a regular problem on a lot of later VAG TDI engines and yes it is mostly due to failure of the boost control actuator diaphragm, often called (incorrectly) the waste-gate which is applicable to the older systems and that used on nearly every petrol engined production car (who can tell me what the PRODUCTION car exception is, well are?).

Anyway, this actuator is replaceable on many VAG models BUT unfortunately not on the Borg Warner BV43-0109 used on the BRD code 170PS engine. We have to resort to a new (not exchnage) replacement turbo from Audi (or TPS) which is part number 03G 145 702 H and this is £1625.70 inc. VAT or buy a unit from an approved Borg Warner supplier such as BTN (http://www.btnturbo.com/) Turbo (http://www.btnturbo.com/) or SCM Turbo (http://www.scmturbo.com/) , the BW part number being 5303 988 0109.