[s-cars] Help with Pressure testing

[Dave Forgie]

Kirby:  I was using a 12V (cigarette lighter-powered) tire pump.  Noisy?  I
don't think I could hear a 747 on take-off.   I had hoped to get to 10 psi and
then stop the pump and listen for leaks.  Not happening. No pressure to leak.
More sleuthing required.

Dave F.

Kirby Smith wrote:

> When I last tested my car, I only plugged the line to the cam cover.  I
> had always assumed that the throttle fully closed and therefore that the
> test didn't depend on the valves, but your point about the ISV is a good
> one, as there should be leakage there, thus at least one valve would
> have to be closed on every cylinder.
>
> Are you using an air compressor or a tire pump?  You should be able to
> hear where the air is leaking if your compressor is adequate and not
> next to your ear.
>
> kirby
>
> Dave Forgie wrote:
> >
> > S-gruppees:  It finally stopped raining here in Vancouver and the sun
> > came out (after it burned off the fog).  I decided to pass on lawn
> > mowing and finally pressure test the intake hoses on my 93 S4.  I built
> > an inlet hose plug from a suitably sized tin can and a Shrader
> > (Shroeder?) air valve.  I knew that I had to plug the cam cover breather
> > so I removed the hose from the cover (at the front of the engine) and
> > used a champagne cork (and the gear clamp) to plug the hose..  Started
> > Test No. 1 - couldn't get any pressure but smelled oil.  Put finger over
> > the metal cam cover breather tube.  Slight pressure.  Decide that I need
> > to plug something else.  Figure its the bottom hose on the idle
> > stabilizer valve (ISV).  Remove and plug hose with a wine cork (and the
> > gear clamp). (Note: all corks were previously used and not fresh from
> > the bottle).  Test No. 2-  nothing.  Not a sausage (as the Brits say).
> > I either have a problem with my test apparatus (I am going to find a
> > plastic plug for the big end) OR, more likely, I am doing something
> > wrong.  Do I need to also remove the hose from the throttle body and
> > plug it?? I had assumed that there was no overlap on the cam lobes and
> > all cylinders were "sealed".  Seems like this could be my mistake.  Any
> > BTDT's (where is the tech FAQ on this??)???  Help!  (Please).
> >
> > Dave F.
> >
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