WGFV, LED Tester and WOT Switch

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <19980714015931.SJIK5552@[166.41.111.73]> Mark Pollan writes:

> Rigged an LED tester per Scott Mockry's page (thanks Scott!) now all
> I need is help interpreting the results.
>
> Bridged terminal 2 and three of the throttle switch and the LED flickered
> for a couple of seconds.  Means WGFV is O.K.?

Nope.

> I have the tester leads long enough so that the LED is right in front
> of me under the wiper.  When I go WOT, what should happen?  LED stays
> lit as long as I am WOT?  If it doesn't that means WOT switch is bad?

Rig the LED to the WGFV itself.   When you got to WOT, it should flicker
continuously.  If it goes either solidly on, or gradually goes out, the
ECU cannot control the wastegate as it wishes.  On the ur-quattro,
gradually going out with increasing speed is a symptom of too much
preload on the wastegate spring - with practice, I've become able to
guess the shim thickness by watching the LED.

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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