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Subject:Re: Surging between 1700 and 3000 rpm
From:Mark Drillock
Date:Sat, 31 Mar 2007 14:23:27 -0800

As suspected, your fuel system can't supply enough fuel for much more
than idling. A quick test would be to connect another fuel "tank" to the
pump inlet and see if that helps. You don't need to drive it, just do a
before and after test of fuel delivery as described earlier in the
Bentley. Measure how much fuel comes out of the return line in 30
seconds. Bentley says 500 ml, the size of an ordinary serving bottle of
drinking water.

Mark

mordo wrote:

> Yes, o2 sensor has no effect, connected or not. Checked distributor - it
> looks good. I put a new eye on the ground for good measure.
>
> I measured fuel pressure at the T both with and without vacuum connected.
> Both are at spec. However, under load, both with and without vacuum
> connected, the pressure drops precipitously to almost ZERO.
>
> So, FPR, fuel pump or restricted filter? I will start with the inexpensive
> and easy filter because I am already suspicious of this one.
>
> Would the FPR malfunction both with and without vacuum connected?
>
> Also, I know this has been debated but what's the consensus? Filter before
> AND after the pump or just before the pump?
>
> ciao,
>
> mordo
>