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Re: Fuel injection questions

> a) I used the on-board diagnostics to run the fuel pump and warm-up valve.  
> Then I applied vacuum to the pressure regulator.  The fuel pump noise 
> rose in pitch, quite noticably.

Careful doing tests running the fuel pump by on-board diagnostics - there
is some funny code in the MAC11 computer at least - I think it cycles
the power to the fuel pump at a 50% duty cycle.

> A bigger surprise came when I measured system pressure.  I had hypothesised 
> that the two were brought under one valve's control on the MB to allow system 
> pressure to be increased as control pressure is decreased as a result of the 
> vacuum input.  WRONG!  System pressure drops almost 1.0 bar with 0.5 bar of 
> vacuum input.

Ah, but what happens when you apply pressure to it?  One would expect an
increase in system pressure in this case.

BTW, for us US types, what is the spec for HP and max boost for your car?