2002 1.9 Limp Mode/turbo swoosh

[gwairways]

Hi everyone, I'm new to the forum and new to TDI's (my second day owning it). I just purchased a 2002 golf tdi, the ALH model, and am having issues already. On my way home from the dealer, I was on the freeway and started to go uphill, to keep up speed I push the pedal in a little more and the turbo seemed to just 'go out'. I also noticed when just driving around anywhere, when the turbo kicks in around 3k a loud 'swoosh' noise starts and gets louder as the rpm gets higher. When I turn the car off, then back on again the turbo is back and normally operating.

As a little background in myself, I'm not new to turbos. My previous car was a Volvo s70 which i modded a bit and even put a T5 turbo in. So I know the sounds the turbo should make. The sound that is coming from my TDI, however, sounds almost as if there is a leak somewhere in the system. The check engine light does turn on after the car goes into limp mode. I pulled the code and it's showing a P1556, "Charge Pressure Control - Negative deviation". I have tried disconnecting the MAF to see if the cars power will make a difference and it still goes into limp. I tried looking over all the vacuumed hose's and they all seemed to be okay (although i would not rule that out at all). I tired starting up the car and listening for a leak, but the engine noise is loud and I just cant tell if there is one or not.

If anyone has any idea of what it could possibly be, that would be great. I am mechanically inclined and don't mind doing the maintenance on the car, just I'm not sure where to start with this tdi.

BTW the car has 98,xxx miles on it, with a fresh timing belt/everything that goes with it kit, done. All the vaccume lines looked good, but they are all the cloth covered kind so it's hard for me to detect a leak

[Seatman]

Get checking the boost pipes and their connections, it definitely sounds like you have a leak, I had the same noise the other day from not refitting one of the clamps down at the IC. You might also hear the noise revving the engine in neutral in which case a helper would be handy to try and identify the area.

[gwairways]

Ok I may have found the problem. Before I bought the car I had the dealer ship replace the timing belt and everything in that area. So I got to looking around in there and I was running my hand across the intercooler pipe and where the rubber meats plastic pipe, I felt a gasket or seal hanging out of the connection. Could this be my issue?

[rmchambers]

Yes that doesn't sound right, the pipe should slip over the hard plastic part and those sturdy clamps latch down to keep it all secure. Not sure what gasket would be there but it doesn't sound right!

[gwairways]

After a little more research when I got off work, I found the part number for the o-ring between the plastic and rubber pipe. It's 3C0145117. I'm going to take the hose off tomorrow and see what it looks like. I also read a few other places that people will take the IC pipes off while doing the timing belt, so that would explaine why the car acted normal on the test drive, then not after I purchased it and had the maintance done.

Will keep you posted!

Thanks for your quick replys!

[Seatman]

I've no idea what this O ring/seal is you've found, never seen one on an ALH boost pipes. I wonder if yours has the PD 130/150 manifold and someone has fitted different pipes. Here's the standard set up



That squarish looking pipe and the elbow to the intake are the ones that get removed for the timing belt.

[gwairways]

Oh okay I see what your talking about. The pipes I'm talking about are the pipes between the turbo and the intercooler on the bottom of the car (before the air hits the IC).

[Seatman]

On the one that goes to the IC? The one coming from my IC is exactly the same kind of fitting as the elbow at the intake.

[Genos]

Some of the replacement turbos come with an upgraded pipe to the kinda flattened piece going to the intercooler. The quick release end has a green? 'O' ring on it to seal the pipe.

[gwairways]

Just wanted to let everyone know the car is fixed and running strong again. It was indeed the o-ring (3C0145117) the goes between the turbo and the intercooler, just after the elbow pressure Pipe coming out of the bottom of the turbo. I talked with VW and it's a common seal that will breaks if not replaced every time the pipes came off (like when the timing belt is done).

Thanks everyone for your help!