Guys,

A mates got a superb in work, getting the error:

"Fault code: 00575 intake manifold pressure value below control limit"

Drives, but no boost!

Any ideas what could be wrong?

Well, possibly damaged turbo, inoperative turbo vane actuator, hole in the intake tract, vacuum hose to turbo actuator control valve popped off, to name but a few.

First check the intercooler and intercooler pipework for holes, and the vacuum hoses to turbo and adjacent valve. Best to check that the actuator on the turbo is moving when the engine is revved. you need to take cover off the engine (just pull off), and then remove thermal cover on turbo - it is held with 3 screws.

Edited 24 June, 200916 yr by dieselV6

He's done the first few things you've mentioned, But hes gonna look at the actuator now!

Will get back to you if no joy!

The actuator is moving when revved but still no joy!

Any ideas?

Have you cleared the code? It could be in limp mode until the code is cleared.

But if vacuum actuator works, then it's either damaged turbo or a hole (air leak) between turbo compressor and engine air intake. If you can hear the turbo spinning without any new sound effects it's likely there's a hole you have not found yet

Check all the hoses running to the airbox and any on the bulkhead, if he's changed an air filter recently it's almost certain a hose is still off somewhere.