Schumi1

The variable intake runner butterfly shaft thing is locked up on one side and the controller broke. Is this a big deal to fix and is it necessary that I fix it asap?

4Driver4

I have an intake from a 1999 2.8 sitting on the shelf in my garage.

Edd W

and the mechanism can seize but can be freed off using something like WD40.

4Driver4

Much easier than swapping the manifold. Controllers are not cheap, IIRC.

Edd W

Is it not controlled by the engine management ECU?

Schumi1

2001 A6 4.2 Quattro

4Driver4

I assume he means the vacuum thingie.

4Driver4

Can't help you there...unless the actuator is the same (which it might be).

Edd W

I guess the design for the 4.2 will be similar to the 2.8. There should be a linkage from the lever which is linked to the flap that goes to a vacuum diaphragm unit. If you detach this does the flap move or is it that which is stuck or seized?

Schumi1

Will one side working and one not hurt the engine? Fuel economy?