Interesting ur-quattro problem

[Phil@sievers.com (Phil Payne)]

In message <199706171808.LAA12388@gonzo.wolfenet.com> Orin Eman writes:

> Funny thing is in the MAC11 computer, all those grounds that go into the
> computer are then tied together immediately... you'd think that they would
> use some kind of differential amp to cancel out any potential on the
> engine or main computer ground, but no.  For example, I measured my
> O2 sensor between the sensor wire and the sensor body, it was doing its
> thing in the .08 to .88 V range.  Fine.  At the computer, it showed
> -.08 to .7 V!  There was a significant difference between the engine
> ground and the computer ground!

Well, we suspect the MAC12 to be similar - but there's no OXS
sensor anyway.  All of the MAC12's sensors are block-mounted, except
the post-intercooler air temperature.

--
 Phil Payne
 Phone: +44 385302803  Fax: +44 1536723021  CIS: 100012,1660