CIS Diagnostic, help

[Steve Sherman]

Ben:

Pretty sure it is the system pressure.  I did not mention it, but I had the
valve in the test rig shut at first.  That is supposed to give system pressure,
as the fuel cannot pass thru to the control regulator and the return line....
I also tried with the test valve open, and that was a few #'s lower, which I
think is per spec, but I don't know what (if anything) it means if your system
pressure is low.

Did get the right fittings to check the pressure at the filter.  It reads the
same as the system readings 40 easing up to 50#, instead of the 90# or so it
should be.  Also I noticed that the pump making a repeating cycle of high vs
lower speed as it was pumping, as though it was hitting air for a bit then more
gas.  Since the tank is full, I am thinking that it may be a clogged screen or
failing pump.  In either case something I can try to tackle here in the
driveway....

Thanks again...

Ben Swann wrote:

> Steve,
>
> It sounds like you are reading the control pressure, in which case may be
> on the high side for an engine not fully warm - check Bentley for exact
> pressure vs. temp.
>
> The fuel pump aka system pressure should be more like 90 PSI.
>
> Ben
>
> On Monday, May 06, 2002 10:41 PM, Steve Sherman
> [SMTP:spsherm at attglobal.net] wrote:
> > Bernard
> >
> > Thanks,  I have been taking the presuure readings per Probst and the
> meter
> > instructions; the meter goes between the fuel dist and the warm up
> regulator
> > (aka control pressure reg).
> >
> > I reran the test again tonite, both pre and post a new fuel filter.  Same
> > numbers, both ways.  There was a short (1-2sec) spike up to 70# but that
> was it,
> > then the numbers held at 40-50#.
> >
> snip
> >
> > Steve