Turbo Leaking Air?

I bought this 99 new beetle about a year ago, from what I could tell it hasn't had a lot of in-depth maintenance and I find myself replacing things here and there.

Recently, the car started sounding like it was turning on a fan when the engine would go under load. At first I thought that maybe the rpms had to do with the AC fan or something along those lines and I just hadn't noticed it because its been a really hot summer. However, I went up to the mountains last weekend and twice, the turbo turned off when climbing hills. After pulling over and restarting, it worked fine both times. The engine also threw code P1550. I just replaced the vacuum hoses(they looked like they were falling apart), but it didn't change anything. The fan noise happens whenever the turbo is turned on, and feels as if its dumping half it's boost constantly. Is there any way to easily diagnose an air leak somewhere? I've read that this might be the intake gaskets, is there some way to be sure?

Could be a sticky vnt mechanism, that power cutting out is limp mode, the ecu shuts down the power to protect the engine.

http://wiki.ross-tech.com/wiki/index.php/17958/P1550/005456

I'm about to see if I can test the VNT, but after getting under the car and checking stuff out I noticed two things, 1st, the lower intercooler pipe looks to be leaking a bit. The lower end is wet with oil while the upper end of the pipe is dry. 2nd, it looks like the entire back side of the engine is damp with oil, again leading me to believe the intake gaskets? I'll keep looking to see what I can find, but if anyone knows about these two leaks I would really appreciate your input.

Edit: I think I found the source of the air noise, while examining the egr area for leaks I saw the short rubber pipe connecting to the egr cracked.

There you go. Good find.

How would you go about pressure testing this system if the crack had not been found?

You have to create a load on the engine while listening for the leak.
The safest way is to raise the front wheels securely and have a helper brake while
applying some acceleration and see if you can hear the leak under the hood.

On the oil leaks, be sure to drain your IC piping. And as to oil on the backside of the engine, check to see if you're getting oil out of the EGR valve's weep hole (it faces the valve cover- you can see it from the front of the car- it's a small hole); if things aren't oily from there then it might be the EGR valve o-ring (between the valve and the intake manifold) or the valve cover seal is compromised.

You have to create a load on the engine while listening for the leak.
The safest way is to raise the front wheels securely and have a helper brake while
applying some acceleration and see if you can hear the leak under the hood.-YIKES!!!

Not the safest, not at all. Plus you really can't hear a slight boost leak with the motor running...

The safest way is found on here using an air compressor (with integral air tank), a two dollar pneumatic fitting, and a PVC end cap. The motor is off, and you can do it all by yourself before you end up on someone's YouTube video.

I did it and found that I didn't connect my upper intercooler pipe well enough, it was the cause of my limp mode/black smoke. Though, the barbs on the pipe MAY be wearing. That's my story and I'm sticking to it'll.

We seem to disagree with the definition of 'securely'.
I have done this on my mechanic's chassis lift. Very secure and safe.
You don't need to rev much, either. Just enough to build some boost.
Since you can often hear the boost leak from inside the car,
we disagree there as well.

UhOh said:

On the oil leaks, be sure to drain your IC piping. And as to oil on the backside of the engine, check to see if you're getting oil out of the EGR valve's weep hole (it faces the valve cover- you can see it from the front of the car- it's a small hole); if things aren't oily from there then it might be the EGR valve o-ring (between the valve and the intake manifold) or the valve cover seal is compromised.

Click to expand...

I just got the new hose today, put it on, reset the error code and took it down some back roads to start the readiness checks. The entire EGR area was covered in oil. After putting on the new hose I cleaned up that area before driving it. So far its staying clean and the bug runs perfect at the moment. Will look under the car soon to see if its staying dry. Is it possible the loss of pressure from the cracked hose was causing the EGR to keep that valve open and leaking oil out the weeping hole?

As for the lower IC pipe, I did detach it to drain anything that might be in there, but there was nothing. it was damp on the bottom but there was nothing in the hose other than the sides being damp with oil. Is there anything to be done about this? There doesn't seem to be any types of seals to replace other than the short rubber hose on the bottom.

The weep hole leaks because of an internal seal that gets weary. To stop that you’d have to get a new egr. Which may be necessary down the road or when you get tired of it weeping.

The lower hose is perfectly normal to have an oil film on the inside, where you run into trouble is an accumulation of oil in the lower intercooler and intercooler hose.

Tdijarhead said:

The weep hole leaks because of an internal seal that gets weary. To stop that you’d have to get a new egr. Which may be necessary down the road or when you get tired of it weeping.

The lower hose is perfectly normal to have an oil film on the inside, where you run into trouble is an accumulation of oil in the lower intercooler and intercooler hose.

Click to expand...

Understood about the EGR, but with the lower IC pipe what I was thinking was an issue is the outside of the hose/pipe is also damp with oil not just the inside. Haven't had the car drip in a while but it definitely seems like there's a leak around that area, is that normal?

Mine doesn't seem to leak a drop. I find it strange that the egr hose cracked like that. I know it's old and I guess heat and cold could crack it. I have a weep but rather than being gung ho to replace the unit, I'll clean it up and hope I can tolerate the result. I'm gearing up for an intake clean and turbo swap. The trauma!

Just a quick update on the leaking EGR weep hole: after driving it for the past week at least ~50 miles every day, the weep hole is still clean with no signs of oil leakage since replacing the cracked hose. Still haven't been under the car to see if the back of the engine is wet or dry, but I think we should consider that another possible cause of a leaking EGR weep hole might be because of a leak somewhere in the intecooler hoses. Granted, the leak in my hose was bigger than most so it may have been a special case.