Help needed with RS2 turbo...

[Martynf]

Guys, need your advice on a friends RS2 problem.

RS2 in question has zero turbo boost at all by the seat of the pants dyno! You wait for 3K to come up and the big bang, but nothing all the way to 7000 rpm, it's as flat as a pancake!! I drove it this morning and it is completely flat! no turbo boost at all!

Here's the details:

Chipped by AMD
There wasn't a nut on top of the wstegate, ie it looked like a stock wastgate to me.
The hoses have been pressure tested and came back ok.
New OE dump valve + Lambda.
New WGFV being fitted to be sure...

A Porsche trained experienced tech has had a look at it and pressure tested it, but no fault could be found.

I haven't got VAG COM so cannot read any faults codes.

The car is in at a dealers soon for a free (ish) diagnostic session, so I've advised to pull the motor fuse to clear the memory and store any fresh fault codes.

Can anyone suggest anything please??

It appears not to be a leak and the symptom is ZERO turbo boost.

New RS2 turbo fitted only a short while ago and is 'expected' to be ok, so why the zero boost?

All ideas gratefully recieved. Thanks Guys!
Martyn

[Pisobiker]

Martyn, even if WGFV wasn't run by the ECU or was unplugged/broken, the engine should at least boost the "safety" value of ~05-06 bar.
I'll suggest you veryfy at least this.
If no boost at all and car runs smoothly most probable fault could be a mechanical one, WG related.
Open it and verify gate doesn't stuck open and/or spring isn't broken.

If you still get the "safety" boost, then an electronical fault is more likely to be the reason. ECU cuts out if it detects too much boost (which is not the case )or if there is a big leak (which is not the case either). Then should go in "safety" mode if detecting knock (one of the two sensors could be disconnected or just broken) or too high temperatures through both the Temp sensor on the back of the cylinder head, or the multifunction temp. sensor on the water rail under IM.
Without the VAG COM (I think I'll need to buy one as well), is unfortunatly a matter of tryal and error.


Marco

[Martynf]

Thank you Marco!

That gives me a few things to check out.


Martyn

[Doug_RS2]

Torn diaphragm in the wastgate?

Get a hose on that unused pipe and see if you can create a vacuum by sucking.

[Martynf]

Kinky! ;-)

Would the diaphragm cause that as well then? If you undo the nuts holding the top half of the W/G down, is there anything to watch for? or just straight forward, undo nuts and change diaphragm?

Martyn

[Mihnea]

Martyn, I don't think that a torn WG diaphragm would cause this to happen, I'd rather say that the hose from the IM to the ECU isn't tight or something nasty happened to the turbo.... but without any fault codes, it's really hard to tell actually....

Keep us posted,


mihnea

[Martynf]

Thank you Mihnea!

One day I'll get VAG com... oh btw, do you have a standard WG spring available? a friend of mine wants one for his 3B?

Martyn

[S2central.net]

Check the fuse for the WGFV - can't remember which one off hand... its listed on S2 Central in the tech section. Pull fault codes with a LED until you get VAG-COM.

Would also be useful to run output tests - with or without VAGCOM - then you can hear all the actuators being tested.

May also be a leak, but am in the dark without fault codes. I mean I'm good, but I'm not THAT good

Paul

[jubjub]

don't know if its VAG COM or not , but got amate to check with a little hand held thingy (not vert technical iknow!!) came up with the following 00519 and 00561 ( are these right??).

[Mihnea]

2413 (Blink Fault Code), VAG1551/2 Fault Code Number 00561
Mixture Adjustment,
Adaptation limit exceeded,
Symptom: Rich mixture, increased fuel consumption


2222 (Blink Fault Code), VAG1551/2 Fault Code Number 00519
Pressure sensor
ECU Pressure sensor defective,
Repair or replace ECU


So I guess you must have a huge leak in the intake system, possibly the MAP sensor is bad but it's quite unlikely actually...


HTH,

Mihnea

[jubjub]

Mihnea - can you expand on this a bit more....does it mean that a new ecu might be called fo???

[Mihnea]

ABSOLUTELY NOT before performing a thorough pressure test on the whole intake system, running output tests and even then, in case the ECU keeps on throwing this code, you can just swap the MAP sensor, not replace the ECU as the damn stupid Audi fault code list suggests!

Is the ECU stock or chipped?

Mihnea

[jubjub]

it was remapped by AMD about 15 months ago....Who is able to carry out the tests...

[Mihnea]

Mr S2Central.net is being asked for at the shop's counter, we have a man that seriously needs your help!


Contact him, he should be able to help you!

Mihnea

[jubjub]

S2 central..... looks as though i need your help...