jrr6
Member
I have a 2000 Jetta TDI 5-speed with 105k miles. Recently, it has been losing power (and going into limp mode) when I try to accelerate up a hill at highway speeds. Sometimes CEL comes on; I had the dealer read the code and it was P1556 -- Boost deviation negative, intermittent.
Upon reading some of the articles here, I replaced the MAF, and the dealer replaced the N75... still the same symptoms.
After reading yet more posts here, I bought a Mityvac and hooked it to the turbo actuator, and it looks like the linkage barely moves under vacuum -- maybe 1mm at -20psi. The linkage is at the top position, and it looks like the space down to the stop is about 10mm or more. I can't move the linkage with my finger either.
Some of the threads here say you can work the linkage back and forth to loosen it up... but how hard can you/should you push or pry on the thing to do so? (with the actuator attached; I don't have the tools to take it off) I assume it is really supposed to move through the full range, but if it's stuck in one position why don't I get the CEL constantly?
The other weird thing is that I had the turbo replaced (by the dealer, under warranty) just 30K miles and 2.5 years ago. Could the thing really be stuck up that bad that short a time?
Thanks for any advice.
Upon reading some of the articles here, I replaced the MAF, and the dealer replaced the N75... still the same symptoms.
After reading yet more posts here, I bought a Mityvac and hooked it to the turbo actuator, and it looks like the linkage barely moves under vacuum -- maybe 1mm at -20psi. The linkage is at the top position, and it looks like the space down to the stop is about 10mm or more. I can't move the linkage with my finger either.
Some of the threads here say you can work the linkage back and forth to loosen it up... but how hard can you/should you push or pry on the thing to do so? (with the actuator attached; I don't have the tools to take it off) I assume it is really supposed to move through the full range, but if it's stuck in one position why don't I get the CEL constantly?
The other weird thing is that I had the turbo replaced (by the dealer, under warranty) just 30K miles and 2.5 years ago. Could the thing really be stuck up that bad that short a time?
Thanks for any advice.