How Would check for a vacuum leak. I once saw an article but cant remember on which site it was.

 

Does anyone have the address?

 

Thanks

Remove your airbox/filter from the MAF. Cut a small square of mdf to go over the hole and drill four holes so you can bolt it to the MAF. Then drill another hole in the centre and push an old tyre valve through it. Araldite the bolts and the valve securely in place on the mdf to stop air leaks. Then put the assembly on the MAF and tighten nuts on the bolts. Use an air compressor to pressurise the system, careful not to go high, 5psi should do, as you are pressurising some vacuum system as well as boost system. You should hear leaks, or feel them with a wet finger.

 

 

Alternately if you think it is a vac hose leak, remove each hose with the engine running and plug the hole with your finger, listen for a change in engine note. There are hoses on the balance bar, sides of the plenum, under the throttle bodies and on the lower intake pipes.

 

If some larger hoses are leaking check the jubilee clips on: the short thick rubber hose off the turbo, the four large air hoses at the front, if you remove the arch liners you may get a look at the intercooler hoses (this was where mine was), or you may have to take the front bumper off.