My turbo is MIA...

Background:
I bought my 2000 golf TDI a little less then a year ago with about 92000 miles on the odm. I drove it to and from work, about 20 miles each way via highway. I noticed that traveling at about 85mph or about 3200 RPM that the car felt like it hit a STRONG head wind, became very sluggish and had a hard time getting back up to speed. Exiting the free way i could tell that the turbo wasn't spooling up at all. If I were to pull over and turn off the car for about 5 secs and start it again the turbo was back and everything was fine until I reached 85mph or about 3200PRM. This lead me to believe that the MAF or ERG was malfunctioning since A.) The problem disappeared when I turned off the car then started it. and B.) It only occurred at 3200RPM going 85 with increased air flow, not at 3200 at 45 in 3rd for instance. It didn't really bother me too much, since it was rare that i reached 85. It was something I was going to get around to eventually....

Current problem:
But since I bottomed out on a railroad crossing and cracked my oil pan, broke the passenger motor mount, some pulleys, and the shroud fan, my turbo seems to be MIA for the most part. I can hear it spooling at about 2400-2500 but it doesn't provide much boost at those RPMs. It was previously spooling at 1900. I had a local German auto mechanic fix everything that was broken since it was beyond my tools and time, I trust him with my car, he tells the truth and is very fair. I'm really at loss at what could be the problem. I'm sure that my intake needs to be cleaned, but I was thinking that maybe the hard jar of the oil pan hitting the ground could have knocked some crud lose... I'm not sure.

Has any one had similar turbo troubles sans the cracked oil pan/motor mounts etc etc.. Any ideas or testing procedures would be excellent!

I should add that there has been and intermittent check engine light from the start, only after being on the road for a minute or two. Now it seems the light comes on a couple blocks after I start going.

And I also need to get a skid plate. I don't know it it could have completely avoided rail road incident, but i think it might have lessened the damage...

Have you checked the actuator rod on the turbo for physical movement? Easy to do with a Mityvac. Attach to the actuator, add vacuum, and watch for movement. Just less than an inch is normal. Check for smooth movement up to the max movement point.

If the rod doesn't move, spray the attachment point with PBBlaster. Let work for a bit, and try again. Sometimes you have to "persuade" it to move the first time.

If it only moves after 8-10mm of vacuum, it's sticking. Lubricate the rod and the attachment point with a good, lightweight synthetic lube.

Also check that the actuator will hold vacuum if it moves easily and smoothly.

I checked the rod by hand and nothing seemed off. Unfortunately I don't have a mityvac to test it with. I've looked around and found a couple things on Limp mode, it appears that my tdi entered " limp speed" around 85 mph previously, but now it seems to be undercharging the turbo. thats the only reason i can figure why its spooling at 2500 instead of 1900. I might try a couple solutions such as the N75 vacuum fix etc..etc.. I guess it is possible that some of the vac hoses could have been damaged when the engine dropped. I will have to look into replacing some vac hoses. maybe someone sells a kit of hoses.. i could only hope. I'm also going to drive it home today with out the MAF plugged in just to see it that changes the symptoms at all.

after further investigating on this forum it appears the my vac res ( looks like a soft ball) is broken. actually its been disconnected since I bought the car 10 months ago. I might as well replace that while I'm in there replacing hoses.

Paramedick: i found this post of yours about vac hoses

http://forums.tdiclub.com/showpost.php?p=1566427&postcount=30

Will this be enough to replace all the flexible vac hose on my A4 ?

Yes, it will.

Thanks for the info!

UPDATE!!

Last Friday i tried a couple procedure to test a couple of the systems that could be causing the loss of my turbo. Nothing seemed to fix the problem. Upon driving home Friday. My TDI starts to spudder when accelerating. then i hear a "tink" and a sound like i just hit a small object or something like that. I smelt strong exhaust and the sound seemed to come from directly in front of me in the engine compartment. I did a little poking around and found that the down pipe from the EGR cooler to the Exaust man had no bolts or gasket and was loose of course. There also was a little carbon buildup on the bottom of the flange. The sound I heard must have been the bolts and gasket falling. The down pipe is not the main on that comes off of the EGR but the one that connect the chamber after the EGR to the turbo.

Could anyone confirm that this is why I'm having turbo loss...


Its funny now that i think about it, after i got my car back from the shop and the turbo was gone, the car had a little spudder and hesitation @ around 3000 rpm. it must have just been loose...

Further update


In case any is still reading... I stole a bolt from the vacuum reservoir bracket mount and used it for the EGR down pipe to the Ex manafold. Result: power is back to about 80%, and the sputter is gone. I'll have to order the gasket and new bolts from the stealer...

Check all the plumbing from the turbo to intercooler (including the cooler itself) for any leaks from cracks in plastic parts or missing clamps. The intercooler (charged air cooler) is very easily damaged in a front end or bottoming out situation and will often break out a piece at mounting tab locations. Any air leak on the pressurized side of the turbo should turn on a CEL like you are getting.