Re: [DML] vacuum leak?

["Walter Coe" <Whalt@xxxx>]

> you know that
> plate that sits on the W-pipe on the intake manifold?

> would this plate being loose or missing a bolt cause a vacuum leak?

Probably. The two bolt holes dead-end into the casting, so they are not
vacuum leaks in themselves. But with either bolt missing, this will most
likely cause a slight vacuum leak on the side of the plate that is not being
held down.

My theory on this plate's purpose is to cover the access needed to drill
pressure equalizing holes between the chambers. Or is this plate replaced
with some kind of sensor in non-DeLorean applications?

> perhaps this is another
> place where people should look when they have a rough idle....

A more likely place for a vacuum leak is the thin paper gaskets where the
outer pipe ends connect to the intake manifold. I had one leaking a few
weeks ago after replacing the thermostat. The paper worked like a reed in a
musical instrument and was very LOUD, like on the order of a squealing loose
belt. The new gaskets from a vendor were not thick enough, so we made
thicker ones.

Walt