Ben Dur
Veteran Member
so i experienced limp mode for the first time ever.
restarted the car and attempted to induce it because i wasnt actually sure that it was limp mode, as ive never experienced it before. the second time it limped on me it even threw a MIL.
plugged in my VCDS-light and it was, i forget exactly, "charge air control positive deviation. sub line noted intermittent". or something to that nature.
did some research and diagnosed the problem to either the VNT actuator or the VNT mechanism inside the turbo.
when i apply vacuum to the actuator pod the actuator arm begins to move at about 5 inHg and then freezes about halfway through its range no matter how much vacuum i applied.
i reached down there and gave it a little nudge and it snapped the rest of the way. after working it a few times it now moves all the way but it seems to freeze up about 1/2 way through its range before snapping further on its own. it seems to move all the way through its range between 5-17 inHg of vacuum but it freezes up and pops at about 14inHg before finishing its movement.
i have ordered a new VNT actuator, but id like to know if its the VNT actuator which is freezing up, or if the turbo itself need to be cleaned. (as removing and disassembling the turbo would be a weekend job and requires a few additional gaskets etc)
really just wondering what typically causes this symptom, or if it is not necessarily a giveaway as to whats bad.
thanks in advance for your input =D
restarted the car and attempted to induce it because i wasnt actually sure that it was limp mode, as ive never experienced it before. the second time it limped on me it even threw a MIL.
plugged in my VCDS-light and it was, i forget exactly, "charge air control positive deviation. sub line noted intermittent". or something to that nature.
did some research and diagnosed the problem to either the VNT actuator or the VNT mechanism inside the turbo.
when i apply vacuum to the actuator pod the actuator arm begins to move at about 5 inHg and then freezes about halfway through its range no matter how much vacuum i applied.
i reached down there and gave it a little nudge and it snapped the rest of the way. after working it a few times it now moves all the way but it seems to freeze up about 1/2 way through its range before snapping further on its own. it seems to move all the way through its range between 5-17 inHg of vacuum but it freezes up and pops at about 14inHg before finishing its movement.
i have ordered a new VNT actuator, but id like to know if its the VNT actuator which is freezing up, or if the turbo itself need to be cleaned. (as removing and disassembling the turbo would be a weekend job and requires a few additional gaskets etc)
really just wondering what typically causes this symptom, or if it is not necessarily a giveaway as to whats bad.
thanks in advance for your input =D
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