I'm down on boost :(

[karlblues2]

I've just had all my bushes and engine mounts fitted (Thanks Martyn F ) And due to that, the exhaust was rubbing and not fitting anywhere and basically needed a new one. I've gone back to a 2.5 " down pipe (thanks to advice ) and a 3" system with a high flow cat. Trouble is, I picked it up today, and can't get more than 16lb/ft of boost. Prior to taking it in, the standard 4th gear, 60kmh flooring would produce 19lb. I've had all the hoses tested and the exhaust tested and there are no leaks ....so where's it gone The turbo was rebuilt 4 months ago so that SHOULD be fine. The wastegate was tested at the same time and found to be fine. This is not good. Any ideas what it can be To top it all, the drivers side electric window cable assembly s*@t itself and now I need to spend more money topping up Martyn's slush fund at VAGPARTS to get a new one Any ideas would be appreciated. Could the chip reset itself Would getting a homefries solve it Or a new turbo

[S2central.net]

What is this 'Hi-flow turbo' that you speak of ?

[karlblues2]

What is this 'Hi-flow turbo' that you speak of ?

Hi Paul
It's merely a K24 rebuilt with slightly better flow. Bigger splines I think Personally, I don't think it's much different to stock, more marketing from the turbo rebuilders www.gcg.com.au
Was working fine and holding 19lb of boost (indicated on the boost guage)
Anything to test

[Josh-stateside]

Hi karl

It sounds like you could be loosing boost becuase of the 3inch system. If it's escaping too fast your not creating enough back pressure to keep the turbine spinning.

But first would be best to pop codes and see what the ecu has to say.

http://www.sjmautotechnik.com/trouble_shooting/20vboost.html

Could they have accidently not plugged the wastegate soilnoid back in? could it be running just on the spring? could they have installed the wastegate solenoid wrong?(there is a right and a wrong way) Could they not have pluged the carbon canister vavle in?(dumps excess fuel vapors in at wot). These are all things that you have to ask yourself. But before you go nuts check the ecu fault codes. Could they have installed the by pass vavle in back wards?

CHeers
josh

[karlblues2]

Hi karl

It sounds like you could be loosing boost becuase of the 3inch system. If it's escaping too fast your not creating enough back pressure to keep the turbine spinning.

But first would be best to pop codes and see what the ecu has to say.

http://www.sjmautotechnik.com/trouble_shooting/20vboost.html

Could they have accidently not plugged the wastegate soilnoid back in? could it be running just on the spring? could they have installed the wastegate solenoid wrong?(there is a right and a wrong way) Could they not have pluged the carbon canister vavle in?(dumps excess fuel vapors in at wot). These are all things that you have to ask yourself. But before you go nuts check the ecu fault codes. Could they have installed the by pass vavle in back wards?

CHeers
josh

Thanks Josh
I've had the car run up with the VAG COM and checked all the valves and solonoids as u suggest. No fault codes came up anywhere. Two issues I'm wondering about. First, would a deeper than standard paper filter make a difference Second, would the thinner oil 0w 20 (which I'm about to change) make a difference
The engine revs fairly smoothly and idle is steady. It just won't pull full boost Could it be the turbo again already In 4th gear at 60km/h flooring it does take a long time to spool up now. Is that significant
Many thanks for your help
Karl

[PeteRR]

Second, would the thinner oil 0w 20 (which I'm about to change) make a difference

0W-20!, surely far too thin!!!!!

[karlblues2]

0W-20!, surely far too thin!!!!!

So people keep saying, but, I still don't know why, or what symptoms / damage it could cause. It's fully synthetic Fuchs GT1. Oil pressure has remained fine and I'm not getting noisy tappets when the engine's hot.
I will change to a heavier oil next week but can someone possibly explain what the problem is with having oil of this viscosity in the S2 Many Thanks
Karl

[PeteRR]

So people keep saying, but, I still don't know why, or what symptoms / damage it could cause. It's fully synthetic Fuchs GT1. Oil pressure has remained fine and I'm not getting noisy tappets when the engine's hot.
I will change to a heavier oil next week but can someone possibly explain what the problem is with having oil of this viscosity in the S2 Many Thanks
Karl

It would seem to be an oil for ultra modern engines, especially small capacity high revvers.
The Audi I5 Turbo is not a 'new' design and needs an oil with a certain amount of 'pumpability' to circulate around the engine.
I doubt an oil of that viscosity would provide long term protection for the engine. Better to stick to at least a fully synth 5W-40, or better still Castrol RS 10W-60.

[karlblues2]

It would seem to be an oil for ultra modern engines, especially small capacity high revvers.
The Audi I5 Turbo is not a 'new' design and needs an oil with a certain amount of 'pumpability' to circulate around the engine.
I doubt an oil of that viscosity would provide long term protection for the engine. Better to stick to at least a fully synth 5W-40, or better still Castrol RS 10W-60.

Excellent. Makes sense now. I have used both Mobil 1 and Castrol RS previously and will use those again now. Many thanks
Karl

[Martynf]

Karl, you have mail.