[urq] MAC 02 Pressure Transducer failure & Timing pin questions

[fdekat]

Hello All!

I've checked the line, and It's good. BUt absolutely NO output when measuring
on the output of the transducer.

I've 'sort of' worked around the problem by running the highest octane gas
that I can find (sunoco 94), and by supplying a 'fake transducer' signal to
the ECU of about 4 volts. Make the ECU think that there is 'some' boost.
Between that, and the 94 gas, it's not pinging too much. An OK short term
fix, but kind of a kludge.

My long term fix is to change the MAC 02 ecu for a MAC 11 ecu and harness
from a MC motor (As a previous owner already swapped in the MC motor, I may
as well finish the job!)  

Presently runing the WX's motor ECU on a MC motor, with an indertirminate
flywheel.



I'm wonering about the flywheel reference pin. As far as I can tell from
research, the WX and the MC have the flywheel pin placed 2 degrees
differently from each other. (And I don't know which way, relative to each
other)

1) I have no way of telling if the flywheel in the car presently is even the
correct flywheel for the car ECU (WX flywheel), or if it's  a flywheel that
belongs to the motor (MC flywheel). So it could already be wrong. Or not! Who
knows?

2) Looking at the IST documents, It looks like the WX ECU can change the
timing by over 30 degrees (From full vac, to full boost around 3-4000 rpm).
I'm thinking that the difference of 2 degrees between the flywheel reference
is of little consequence, compared to the range of adjustment the ECU has.

Sure the ECU won't be where it thinks it is, but I can't see that 2 degrees
making much of a difference.

Any thoughts?

=Frank de Kat=



>Fyi-I got massive pinging when I developed a leak in the pressure hose from
>the IM to the pressure transducer.  Test this line, and the tee to the boost
>gauge for leaks if you haven't already.

>HTH,
>Jim 

-----Original Message-----
From: urq-bounces at audifans.com [mailto:urq-bounces at audifans.com] On
Behalf
Of Buchholz, Steven
Sent: Friday, July 08, 2005 6:02 PM
To: urq at audifans.com
Subject: RE: [urq] MAC 02 Pressure Transducer failure?

.. doggone ... missed on point ... sorry for the follow on ...

One of the other things to beware of is that the reference pin location is
different for a WX and an MC engine ... it is not a simple matter to wire a
MAC-02 onto a WX engine unless you accommodate this change ...

Steve B
San Jose, CA (USA)