does any mod...

Ameer Antar ameer at
Tue Dec 5 04:04:35 EST 2000

>Please read Probst's "Bosch Fuel Injection and Engine Management"
>section 5.2.  The pressure on top of the plunger is controlled
>by the 'control pressure regulator', aka warmup regulator.
>The frequency valve controls pressure difference across the
>metering slit.

yes, you are's a similar idea of changing pressure over the 
plunger, although this way I believe it's a more accurate adjustment.

>The ECU doesn't care about o2 sensor readings for manifold pressure
>above around 1.1 bar (RPM dependent).  It goes open loop regardless
>of the WOT switch.  (Loss of performance due to the WOT switch
>failing is due to the ECU not controlling boost, not fuel issues,
>unless you are below the 1.1 bar or so level.)

never heard of that one. Where is this from? In that case what is the D.C. 
of the freq. valve during 1.1+ bar running? It is my understanding that the 
WOT switch causes open loop mode....

> > In a modified vehicle, at 1.4 or 1.6 bar the A/F ratio should still shoot
> > for the stoich 14.7:1 ratio. The WOT switch allows for a richer mixture 
> not
>Not.  See above.

Well if the air-flow sensor cone is calibrated for stoich A/F ratio, it 
would still be in that neighborhood, w/ or w/o the lamda control.

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