Thread: Odd problem

I had similar problems with ruff running. I had a vacuum leak. I ended up changing all vacuum hoses. It was not a costly exercise. The one that was leaking was the one that goes to the vacuum switch on the fuel line. It is located on the back of the intake plenum on the drivers side. It is really easy to miss but it gets hot so it probably deteriorates the fastest. Mine is a 3.5lt but i assume the 3.9 has the same setup.

Originally Posted by Jazzman

I had similar problems with ruff running. I had a vacuum leak. I ended up changing all vacuum hoses. It was not a costly exercise. The one that was leaking was the one that goes to the vacuum switch on the fuel line. It is located on the back of the intake plenum on the drivers side. It is really easy to miss but it gets hot so it probably deteriorates the fastest. Mine is a 3.5lt but i assume the 3.9 has the same setup.

Yer those vacuum hoses have already been changed but my flapper has been played with a lot in the past so it will take time to find a happy medium


Adam