re. Intro and a couple questions(chip/mileage)

[ben swann]

I recently purchased a Lehman chipped avant and it is exhibiting
similarly abysmal fuel mileage IMO when compared to the QLCC chipped
avant - almost 10 MPG less under similar driving.  I have replaced
thermostat and checked things out, and beleive this car should be
getting much better mileage than it does. I know with some additional
weight, wider tires and slightly less aerodynamic flared fenders, the
car might be getting a litlle worse economy, but 15 around town and 18
on the highway - sheesh.

I will be swapping out my Lehman chips for Mihnea's set in a few
weeks.  I hope to be seeing significant improvement, but we'll find out.
I'll be sure to post results one way or another.

Regards,

Ben
'91 200 turbo quattro avant - silver 107 kmi
'87/88 pearl 5ktqa under reconstruction
+abuncha' 4000 Q's and coupes in the driveway

[I've been lurking on this list for over a year but
this is my first post, so an introduction is in order.
I have recently put a 3B motor into the '91 coupe
quattro I have owned since 1992.  Yes another
"ersatz" S2.  The transplant was done by 2Bennett.
The only deviations from stock are a chip and an
RS2 intercooler (behind an RS2 bumper).  The car
already had a Scorpion cat-back exhaust and the
suspension uses H/R springs with Bilstein shocks.
Eventually I will do some more work on the motor, but
need to recover financially from this project first.

And the chip is where my questions come in.  It is
supposedly a Lehmann, with 2.5bar sensor.  Once in
a while I will see 20psi guage, more often it peaks
at 18 or so.  2B says that is about right for this
chip, so OK.  But I am seeing horrible gas mileage
in city driving- 15-16mpg.  Cruising on the highway
it is 22-24, which is pretty much what I had seen
with the old 7A engine.  Noticed that during
acceleration, the "instantaneous" mpg on the trip
computer drops to 5... even under light throttle
input.  That seems very unusual.  Do others with a
Lehmann chip see this behavior?  What about with
IA or MTM chips?

I have a VAG-COM.  The only DTC I see is the engine
speed fault, which according to 2B is pretty common.
Initially I did have a Intake Air Temp. fault, which
I traced to an intermittent connection at the sensor
and fixed.  That got me back to the expected 18-20psi
boost, and raised the hwy mileage from 19 back to 23.

So next step is to go to the basic settings function
4, which allows viewing of various parameters.  Two
of them are out of whack.  The engine speed (channel
2) hovers around 60 (600RPM) regardless of the actual
engine speed.  And the Ox sensor channel 8 varies
from mid-teens at idle jumping to 70-80 under heavy
acceleration.  Bentley says it should hover around
128.  2B isn't sure whether these are real problems
or not.  They have offered to look at it, but it is
inconvenient to bring them the car, and besides, I
want to figure this stuff out myself.

So, anyone with a Lehmann chip used a VAG-Com to look
at these settings?  Does these problems seem like
something I should pursue, or even send back to 2B?
I should add that I am very happy with their work and
they have bent over backwards to accommodate my very
picky expectations.

TIA and pleasure to meet you all,
Matt Rooke
San Jose CA
'91cq//20vt
'00S4//30vtt]