Need help from a guru

Short story... My wife is going back to work and wanted another cheap commuter car. She found an original owner 2003 Jetta Tdi alh 5 speed that had been sitting for about a year with a bad injection pump. Went up and checked it over and was happy with it so we bought it and had it towed to my shop. Changed injection pump and it fired up. Go for a test drive, no boost at all. Find out the veins are stuck. Take the intake off (which was about plugged shut) and turbo off and cleaned it out using oven off. Got it freed up and found out my actuator was not holding vacuum. Got another used actuator that came off of a factory turbo. Deleted the egr system and cool and installed race pipe. Long story short I still have no (or very) little boost. I can add vacuum to the turbo actuator and it moves freely and holds the vacuum. I have 27lbs of vacuum coming directly off the vacuum pump hose. I deleted all the other vacuum line and have the one off the vacuum pump on the highest up on the n75. The turbo actuator on the same side of the n75 directly below the main vacuum hose. And then the air box hose on the single spot on the n75. Ok... So the n75 has about 18lbs of vacuum going to where the turbo hose goes too. All the lines connected to the n75 are new vacuum lines. I have fired driving it with and without the MAF plugged in and it don't change.... I'm lost I feel like I have tired everything. Anything else to check? I'm almost to the point or order a turbo. Any help would be extremely appreciated.

A new Turbo might not solve the problem.

Have you done a scan to see what DTC codes are showing?

The issue may be with the N75 even though it appears to be working properly.

Lastly, unless you removed the CHAR of the Turbo and went inside and cleaned out the crud, it's not going to work properly. OC and soot make a good lubricant that will only get sticky when the moisture is gone.

See the soot crud in the pic below? Well, OC will not get that out, unless it is opened up as in the pic. .... That Turbo CHAR was taken apart and cleaned like new. It's been functioning great on a car in Indiana for about three years.

But the veins move easily. I have out about 70 miles on it hoping it would somehow come out of it. The only codes that it's throw in for an open circuit for the egr being removed and no longer hooked up

Also. I swapped out the n75 and other other one that controls the egr and it acted the same. Is there a way to test the n75? And maybe if the relay is working?

2002tdi said:

...
I have 27lbs of vacuum coming directly off the vacuum pump hose...

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Obviously, I don't understand something here. Isn't atmospheric pressure around 15 psi?

Units mixup, for sure. Most vacuum gauges show in-hg. "One standard atmosphere equals 14.7 psi (29.92 in.-Hg)"

Ewww.

How does a turbo even get to looking like that?

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S2000_guy said:

Obviously, I don't understand something here. Isn't atmospheric pressure around 15 psi?

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No I have been told you 2 different people that is about perfect

2002tdi said:

Changed injection pump and it fired up. Go for a test drive, no boost at all.

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Are you sure that it's a no-boost situation and not just a low power situation? Are you getting a code for Boost - negative deviation?

Have you checked the MAF numbers yet? On both of the 2003 TDI's I bought, they were the same as yours, and the MAF sensors were bad on both of them. They would barely read above idle airflow. I know that unplugging the MAF is the defacto test around here, but imho you still need to check it for flow data.

Also, after changing the injector pump, did you set the timing and IQ up with VCDS?

The only other things I would say are, if you're still not meeting specified boost numbers, check to make sure you're actually getting that 18" vacuum at the VNT actuator and not just the N75. This would rule out any issue of the vacuum line collapsing between the N75 and the VNT actuator.

Also, when you used the oven cleaner on the turbo, how did you get the vanes freed up? You didn't force the vanes to move did you? (Like putting a wrench on the lever and pushing it?). I'd pop the 3 nuts off the exhaust downpipe flange and look in by the exhaust turbine to make sure the vanes are actually moving. When the vanes are in the open position, you'll see the tips of them closer to the turbine.

I had a guy with perfect injection pup timing but his cam was off.

What color marker was used to set the timing?

If you haven't had it long enough to monitor oil consumption or have much prior comparison data, I would pull the intake and boost pipes off and do a good inspection of the condition of the turbo play and the turbine blades.
Rather rare, but clogged up exhaust/cat if there may be some "history" on the car.
We always seems to run into some strange things on a new used car.

jettawreck said:

If you haven't had it long enough to monitor oil consumption or have much prior comparison data, I would pull the intake and boost pipes off and do a good inspection of the condition of the turbo play and the turbine blades.
Rather rare, but clogged up exhaust/cat if there may be some "history" on the car.
We always seems to run into some strange things on a new used car.

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Yeah....previous owners try all the common fixes and when that dosn't work they pass the problem off to someone else.

gatz said:

Units mixup, for sure. Most vacuum gauges show in-hg. "One standard atmosphere equals 14.7 psi (29.92 in.-Hg)"

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Thanks! I never thought about the unit of measure being wrong... obviously nobody ever had 27 psi of vacuum.

Yeah, I'm also in the camp of a timing issue. Pump timing off, the car will still run but like a big gutless wonder.
And the MAF. VCDS is needed here.

1) verify your cam/crank/injection timing is correct
2) log groups 1,3,11 to see if boost is matching requested

report back with your findings.

You can do an output test on the n75 to make sure it is cycling correctly. The fact that you already measured 18"hg at idle suggests all is good there.

If your timing is good, the turbo is being controlled correctly you could simply have a damaged compressor or turbine in your turbo. You can take a look at both but the turbine isn't really inspect-able without removing the center section from the manifold.

How old is the fuel in the tank? Gelled possibly?

Lots of different ways to go here.

Fuel is brand new. Ask was in a 60 degrees shop while all this was going on. I'm going to check timing tonight and see what that shows.

So my wife was driving the car from my house to my shop 1/2 mile max.... Said it made a loud pop noise and then shut off... top charge pipe blew off the race pipe and there is oil everywhere. Got everything all pulled apart and the odd thing is the turbo feels fine. The intercooler had probably 2 cups of oil in it.. Now I'm really confused.

did you drain the cooler when you did the intake clean? Also, seals can be bad even though the shaft feels fine. O and take that ccv to the ground and get it out of the intake.

So, to make sure i get it correct, the engine quit when (aproximately) the intake tube came off? Does/will it run now? A couple of cups of oil could be either just prior accumulation over time depending on driving habits or a sign of impending trouble.
Was a real clean engine compartment.
Disclaimer:
(I should have stayed out of this thread. I am not a guru of any sort)