Re: WOT Switch

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

In message <362C3079.70F2@ix.netcom.com> Wolff writes:

> I have found that if you click a working WOT switch by hand while the
> car is idling, the idle will change. (At least on my 4kq). Also a good
> idea to turn off the engine and have someone mash the "gas" pedal to the
> floor and check that the throttle is opening all the way and clicking
> the switch. You also don't want too much tension on the cable or it will
> fail early.

On the MC and MB engines (and a good few others) Audi used a one-piece
WOT switch - not the two-switch job used on the WR/WX, JS, etc.

The one-piece switch doesn't click at WOT - it only clicks at idle.  If
you take it apart, you find a boring standard microswitch is performing
the idle function and the WOT function is provided by two long blades
that are very gradually forced together by a cam - no click.  The
usual failure mode is for the solder at the base of one of these blades
to crack.  IME - usually the outer one.

They're easy to fix, but I now throw them away.  The replacement part
has a slightly improved design.

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