[urq] MAC 02 Pressure Transducer failure?

[SpotatAshleys]

I feel fairly sure that Roger Galvin at www.quattroworkshop.co.uk (or .com)
in Lutterworth, UK, has a contact who can repair ECU's in particular,
failure of pressure transducers. A long way from you but if you get
stuck....
I can't believe there's no one state side who can fix them...
Hope this helps

Keith

'87 WR
----- Original Message -----
From: "fdekat" <fdekat at sentex.net>
To: <urq at audifans.com>
Sent: Friday, July 08, 2005 6:16 PM
Subject: [urq] MAC 02 Pressure Transducer failure?


>
> Hello All:
>
> Last month, I spent a lot of time replacing the head gasket in my MC
motored
> urq.  Thanks for all the tips!
>
> I ended up pulling out the manifolds and head separatly, but dropped the
> whole mess back in as one piece. WAY easier...
>
> Now Mr. Bill Bennet pointed out that there was a good chance that my head
> gasket failure was from 'pingin', and that I had to fix that, or I'd have
the
> problem again..
>
> THat man is a genius, because unknown to him, I HAD been hearing light
> pinging before the head gasket failure. Now that I have replace the head
> gasket, I've been really listening for pinging. I find if I drive near
> concrete walls or guard rails, I can hear the pinging if I'm on it fairly
> hard in mid range revs (3500 to maybe 5000).
>
> SO the next thing is, how do you get pinging, if the computer adjusts
> everything?
>
> Martin P tells me about the known 'pressure transducer failure'.
>
> So today I wired up some leads to the transducer, so I could measure it's
> output while driving.
>
> Surprisingly enough, there was no output. I assume that means the ECU
thinks
> it's seeing full vaccum all the time.
>
>  That cold explain the pinging..!
>
> So my questions are:
> 1) What's the chance that replacement transducers are available?
> (Probably unobtanium, so I may as well go to a MAC 11 ECU and harness, as
I
> already have the block, head and turbo..?)
>
> 2) I'm sure I've seen a spreadsheet somewhere, that shows transducer outpu
t
> vs transducer pressure. Anyone else know where to find that?
>
> I could then substitute the pressure transducer output with a fixed
voltage,
> closer to what the ECU would want to see for near full boost. At least
then,
> It won't ping so much (But have other side effects of never changing value
> either).
>
> 3) Or any other ideas?
>
> It's the MAC 02 with the 'yellow' label, if that makes any difference?
>
> Regards,
>
> =Frank de Kat=
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