I have a boost pattern of like 11-6-11 and it was taking its good ole time getting back to 11 at like about 5500 to 6000 rpm. This made me suspect the pre-contol operation.

To trouble shoot, I checked connections etc. and then finally dicsonnected the vacuum line on the pre-control actuator and used a vacuum pump to see if the actuator moved. Unfortunately I was unable to create any vacuum, just sucked air, so I assume the actuator diaphram is blown.

If the actuator is blown, can it be replaced or rebuilt without taking the entire turbos off or engine out? Please say yes. If no what's the best way to get parts?

Also, if it is blown I assume the vacuum tank will be emptied everytime the pre-control solenoid is opened. Will this impact other functions requiring the vacuum? Whould it be wise to plug the vacuum line or can the pre-control solenoid just be electrically disconnected?

Any help would be appreciated.

Thanks,

Doug

 

Seems kind of weird that this tech page gets so little action.

Can anyone give an opinion on this?

Thanks,

Doug

 

I would say it is a vaccum line leak...check under the black box..hope that helps