More MB thinking

[QSHIPQ@aol.com]

Phil and Orin:

Though the MB doesn't have an o2 sensor, if it has a WOT switch, it really is
the same as the MC in terms of the MAP.  Since the MC assigns a FV value to
the lambda circuit, effectively you have a mechanical injection system (albeit
with more fuel than mechanical alone).  Since the MC can handle some serious
mods with no changes to the fuel system, my thinking is, so can the MB.
Although Orin is probably right that you have a increase need for fuel with
increases in VE, the usual effect of VE in terms of fuel would be seen more
before WOT than after.  What you have to find, is what the MB computer does
with the WOT signal.  My thinking is that it somehow lowers control pressure,
or fixes a value to the fuel pump return (similar to a lambda FV, but
simpler).  Assuming you have a WOT switch, you have control somewhere in the
system.  Period.  If you have no WOT switch then you have a purely mechanical
injection, in which case a move to larger fuel injectors and/or a lowering of
control pressure should accomodate mild to medium performance mods (btdt with
old scirocco <prelamda> FI, used 5kt fuel injectors only, with a light control
pressure adj almost double hp with stock fuel head).  As a rule, the audi CIS
fuel systems should be able to handle 300+hp or so before topping out.
Electro-Mechanical (MB) or Lambda (MC), shouldn't make a difference in terms
of WOT switch activation.  Both are using that switch to fix or assign a
value/s.  You just need to find out the what on the MB.

My thinking is still that you have a different problem, that a sensor is
messing you up.  

Do let us know when it's resolved...

Scott Justusson
QSHIPQ@aol.com