new and need assistance

i bought a 2003 jetta tdi a few weeks ago and really like the car. ive been a technician for 18yrs but very little experience with diesels. Problem: smoke on acceleration and no power at all then when it does accel it act like a gas car would if it had a faulty coil. after a few seconds it clears up and is fine. it would happen once or twice a on my way to and from wrk (140miles). now it almost every acceleration. came on all at once. couple days ago. any direction on where to go??? bad fuel? i have a egr DTC but have had since i got the car. it does seem to have a over all lack of power lately too, but ive only had it a fewweeks but can tell it doesnt have the power it did. any help would be great. like i said i am a technician but knowledge on tdi are very limited. thanks!

Your issues have several possible causes. I'd first check the turbo actuator to see if it goes through its full range of motion. It should start to close the turbo vanes at 2-5 inches of vacuum, and they should be fully closed around 15. And the rod should move smoothly. If not, you may need a new actuator, they do fail with age.

Also, you may have a faulty mass airflow sensor, and the car may go into a MAF delete mode after driving it a few moments. This would be especially true if the car has a chip tune that allows this function. Unplug the MAF and see if it runs better. If it does then the MAF is probably faulty.

Third, check the intake manifold for clogging. Remove the hose that goes to the EGR valve and shine a light inside. You can remove the EGR (3 allen bolts) and see the manifold itself. It will probably look kind of cruddy, but if if the opening is severely restricted it will cause low power.

You should also look for boost leaks in the intercooler system. Look for teltale oil leaks in around the hoses, their connections, and the intercooler. There's oil in suspension in the system and it'll get out if there's a boost leak.

There are several how tos here on limp mode, which may also help you isolate the problem.

2X on the above.

There's a VW bulletin on the actuator rusting internally.

A bit more to test the actuator operation.
T a vacuum gauge (or pump) into the vacuum line going to the turbo.
When you start the car you should get about 12 inches of vacuum to it.
When you take off the vacuum should drop.
There's a vacuum pump on the right side of the head, feeds the brake booster & engine
vacuum controls.
The nipple in the pump gets loose with age, many fix it with silicon or epoxy.
You need at least 20 inches of vacuum for the turbo actuator to go full.
Last, you may be able to reach the actuator arm on the turbo from the top.
While the car is cold have someone start it and see if the arm actually moves.
This would be where you check the movement listed above.
Last check from the bottom the actuator is held on with 2 nuts, take them off.
Pull the actuator down and see of the arm going into the turbo moves freely and smooth.
C-clip holds the actuator to the arm.
Easy to get off, I lost a few clips trying to put it back on.
I tied a length of sewing thread on the clip so each time it flew I could find it.
I'm assuming you do not have VCDS to diagnose it (OBD2)
You have to check how much boost you get.
Engine group - block 11 (iIrc) lists boost actual and requested.
Gives you an idea if you are getting boost or not, as well as to much boost.