[bmklos]

I have had a problem with my 2006 Jetta TDI for some time now, it is only present when the weather is above ~60 degrees. When the car is heated up I can get the car to hesitate in two situations. When I start from a stop sign the car will accelerate and then fall on its face twice in quick succession producing a puff of black smoke and then taking off like a missile. The second situation is while driving at steady speeds and part load; this produces a shudder which in certain situations can be maintained the whole way down the street. The car also has a Kerma tune installed. I have tried the following to solve the hesitation problem:

- Replaced MAF
- Pressure tested intake system south of MAF when the car was hot and was hesitating---no obvious leak
- Replaced vacuum tubing cleaned MAP sensor
- Cleaned all intake piping except intake manifold. There was ~.25” of buildup on the intake piping walls
- Cleaned EGR valve
- I had a separate tune created which turns off the EGR altogether. However, I still prefer to drive the car with the EGR engaged as the car is more drivable and seems to be more powerful. When the EGR is turned off the turbo tends to ‘hunt’ under steady conditions. For example when driving along at a constant speed the turbo will climb in RPM and then release causing car to lurch forward and then the turbo will climb again a short time later.
- Fuel filter has been replace several times
- N75 valve appears to be actuating the turbo vanes correctly (used VCDS to verify)

Over the weekend I replaced the EGR cooler due to signs of leakage around the by-pass valve. This seems to have just aggrivated the situation as the shuddering and hesitation has gone from being a hit or miss situation to something which happens upon acceleration from every stop.

 

[chittychittybangbang]

could it be some other exhaust leak? any signs of soot around engine or under car?

I would start logging maf, egr, and boost, see if you see anything weird.

egr and intake flap move as car accelerates, perhaps some prob with valve? they use plastic gears, have been known to strip, cause weird issues. you can manually move valve and feel the gears turn

 

[zdub]

I have the same problem. It has to be the turbo in my case, because there's black soot all over the actuator and even the CV shaft.

I think the burst of power and surging could be related to the worn actuator lever...

http://www.myturbodiesel.com/1000q/a4/VNT-turbo-removal-vanes.htm

 

[dvw23m]

I'm going to check some of these things. My car does this also, and it drives me crazy. thanks guys

 

[whitetdi2006]

Please Update

I am having the same exact problem with my 06 Jetta, did you find the problem? I am new to the diesel world and I am lost on this issue.

 

[Kszabo]

My 2006 Jetta TDI also experiences these symptoms when going up hills. I just bought the car 300 miles ago, so yesterday I put DieselKleen Cetane boost and injector cleaner in yesterday and have 100 miles on it with it in, and am waiting to see if it works. Also I have a chip in the box coming and will install in the next few days.

 

[Atstodd]

This was the fix for me: http://www.myturbodiesel.com/1000q/a5/turbo-response-adjustment-tdi.htm

My 06 jetta was hesitating a lot especially in first gear from a stop. It would smoke and even knock if I pushed it hard enough, then all of a sudden the actuator would open the vanes and it would take off. I put a wire on the actuator screw and on the vacuum nipple. It took a little bit of adjusting but all hesitation is gone now. I was unable to get the adjuster screw loose even with a crows foot so I had to go the wire route. The guide also mentions using a zip tie but I didn't have one handy.

Also I did the test suggested in the guide but my car was not out of range, limiting the actuator did help massively however.

 

[Dion vw jetta 2006]

Hello guys I live in Belize and am looking for some help. My dad tells me that nothing is wrong but he doesn't drive the car. I have a shudder and heasitiation. My VW 2006 Jetta 1.9 tdi heasitiation and shudder is not a good feeling any suggestions? No power at times when it starts to shudder.