RE: The wonders of the WOT switch

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

In message <000001be6fcd$495468c0$38b935cf@WWICS.wwics.com> "Dan Sinclair" writes:

> My 90 runs alright, idles a little rough and startup, but most annoying is
> that the car will lug down to 400 RPM and stumble back up to idle every 4th
> or 5th stop, and on occasion, it lugs to 400 RPM and can't recover, promptly
> dying.  The other times, the engine decelerates to 1100 RPM then settles
> down to idle at ~900 RPM.  Is this similar to your experience Dave?

Is the stumble down to 400 rpm related to removing your foot from the
throttle _quickly_?

The ISV takes time to respond, and if the little dashpot that slows the
throttle butterfly valve when it's closing quickly is defective, the
throttle can close more quickly than the ISV can compensate.

> While running the Output Checks, I noticed that the Bentley indicated that
> you should hear each component (CSV, solenoid, etc.) CLICK (or cycle) when
> you depress the WOT switch.  On my car, the clicks and cycles started
> WITHOUT depressing the WOT switch.  This lead me to believe that the WOT
> switch might internally be stuck in the ON (depressed) position.  I don't
> have any way to test my theory, but I'm tempted to just replace the sucker
> strait out and see what happens.  What do you think?  What did the switch
> cost?

Those sound like Motronic-type instructions for testing individual EFI
injectors.  Try doing the output checks as per Scott's page.  I don't
think the WoT switch influences the tests on an 88 90.

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
 (The contents of this post will _NOT_ appear in the UK Newsletter.)