On Mon, May 11, 2009 at 5:54 PM, Dave Arthur <dave.arthur@nscc.ca> wrote:

>
> I replaced the relay and connected the pump up properly and all was well,
> until I checked the fuel pressure. As soon as the pump stopped the fuel
> pressure bled down rapidly to zero (~2-3 sec). The manual expects at least
> 29 psi after ten minutes!
>
> I pinched off the fuel return line and individual injectors to test for leak
> down issues and concluded that the pump itself was not holding the pressure
> when it stopped.
>
> So the engine runs, but starts hard, with the pump running all the time as
> before, the engine started immediately.
>

Did you check the fuel regulator?

If it had a faulty diaphragm, fuel might leak past into vacuum line
causing the pressure drop.

Of course having fuel leaking past it into the vacuum line is not a
good thing either!  :)

Neil.

--
Neil Nicholson '81 VanaJetta 2.0 "Jaco"

http://tubaneil.googlepages.com/

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines