[1000rrjon]

I am a new member to this forum, and just bought a 2003 Jetta with the ALH motor, automatic trans.
I'm going through normal maintenance and check over, as the car wasnt maintained very well at all. I have an Overboost condition, putting the engine into limp mode with any type of throttle input. Checking into the boost frequency solenoid or possible misadjusted vnt actuator (hoses are good, vacuum source is good, and vnt vanes arent stuck as of now). Thanks for all the helpful advice and posts so far!

Jon

 

[chittychittybangbang]

Double check the hoses! It's very common that people start chasing the more unusual causes when there's a small split that they can't see. However, your case sounds severe if any throttle input sends you into limp.

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[Seatman]

That sounds like a new one, limp mode with any throttle? I've not seen that yet, I wonder if the map sensor's a bit wonky. I agree with chitty on the vacuum pipes though, I think they should be replaced as a matter of general maintainence especially as it's so cheap to buy the tubing. I would go with the adjustment of the actuator too, here's the faq for replacing and adjusting it if you haven't already seen it.

http://www.myturbodiesel.com/1000q/a4/VNT-wastegate-adjust.htm

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