I would use the vacuum line to the fuel pressure regulator.

Mark

Mike "Rocket J Squirrel" Elliott wrote:

> Hi, I'm looking for leaks in the intake manifold. Bentley's doesn't give
> a procedure for checking intake manifold vacuum so I'm winging it. I let
> the engine warm up so that aux air regulator thing is closed, and then I
>  pulled one of the hoses going to the vacuum unit on the dizzie and
> connected it to my fine Harbor Freight vacuum gauge.
>
> This is a 1.9L engine and the hose I'm using is the hose labeled "2" on
> the left hand photo on page 24.25 in Bentleys.I don't know how
> appropriate this hose is, but it has fewer bits connected to it than the
> other one. There's also a hose going to the fuel pressure regulator,
> maybe it's a better choice?
>
> ANYWAYS, when the hose is disconnected from the vacuum unit, the idle
> hunts up and down. The vacuum gauge shows around 18psi -- depending on
> engine rpms. I can open the throttle and the vacuum might drop to 10psi,
> then climb back up . . . I really have no idea how one goes about
> measuring vacuum.
>
> --
>
> Mike "Rocket J Squirrel" Elliott
> 71 Type 2: the Wonderbus
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
> KG6RCR
>