Date:         Mon, 21 Nov 94 10:51:25 PST
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Dave Kautz <dkautz@hpsidms1.sid.hp.com>
Subject:      Re: Oxygen Sensor / Full Throttle Switch

> David Carment writes;

> Finally when the vehicle was in for emmissons tests, was told by reputable
> VW mechanic that the full throttle setup is marginal at best. He said you
> could remove the device and would not notice the difference. I tend to
> agree with him, at full throttle the difference is negligible; and yes the
> switch is properly adjusted to the cam.
> 
> Conclusion - still unclear what the full throttle switch is intended to do
> : advance the curve, richen the mixture or a combination; believe that is
> not crucial but nevertheless a problem.
> 
> One solution - glancing through Bentley's at the bookstore; they have
>  a detailed description of adjusting and testing the full throttle switch
> and black box - this would be my next step....
> 
> Perhaps some one out there can throw some light on the issue (PhD's not
> required).....DC
> 



  I am always a little specualtive when mechanics start on the "those engineers
  at the factory don't know what they're doing" - I doubt VW would have gone to
  the expense of including the full throttle switch if it wasn't necessary. My
  recollection of it's function (I'm at work and can't look it up) is that it
  tells the computer to richen up the mixture at full throttle. This may not
  result in more power but it may help keep peak temperatures and detonation
  under control. I'd try and keep it working, if possible.

Einspritzerly yours,

Dave Kautz