It seems to me that if the fuel pressure leaks down too quickly, the cause
could be an injector, the fuel pressure regulator, or the fuel pump.  The
first case is more serious than the last two.  You need a way to tell which
it is.

Larry A.

On Sat, May 16, 2015 at 11:35 AM, Stuart MacMillan <stuartmacm@gmail.com>
wrote:

> Easiest way to do the fuel leak down test is with a fuel pressure gauge.
> Bentley says system should hold pressure (30 psi or so) for several minutes
> after shutdown.  If your gauge comes with an open hose adapter, slip it
> over
> the fuel tap near the distributor, and use a clamp.  Otherwise cut it and
> splice it with a brass barbed coupling for other cars. Get the type that
> drains any residual gas out a separate line. Instructions here, including
> safety procedures: https://www.youtube.com/watch?v=QsqBJxKj1KQ
>
> Do it soon, backfires are hard on the AFM. I've used mine many times over
> the past 40 years to diagnose fuel system problems.
>
> Stuart
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Dennis Jowell
> Sent: Saturday, May 16, 2015 3:19 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Start up,back fire?
>
> Question on why do I sometimes get a backfire from my 2.2 GOWESTY WBX.
> yesterday I drove the 88 gl Westy an 1.5 hr pulled over to check my GPS,
> shut the engine off. Then 2 minutes later started it and "bang" it
> backfired, it did start. Shut it down and tried again same thing. Drove
> home
> it didn't occur again. Any thoughts of what is going on? The new  Engine
> has
> about 5000 miles on it. Maybe to many mice running around in there.
>
> Dennis Jowell
> Scotch Hollow Farm
> Newbury, Vermont
>