Re: Throttle switch

[Dave Head <dhead@sundial.sundial.net>]

At 03:12 PM 9/9/96 -0400, you wrote:
>Okay audi-friends,
>
>I tapped on the throttle control switch sitting on the left side of the
>throttle body, and voila.. the idle came back down to normal. 
>
>Today, I pulled the switch off. I tried to get it apart, but the Bosche gnomes
>have epoxed the pieces together. I noticed that the switch, when turned, emits
>and audible "click" at one end of travel, and at the other.. it sticks! 
>
>The part costs about $65 new from Linda. No aftermarket, Bosche original. 
>I think I'm going to try and lube the turning portion with a couple quick
>blasts of WD40 and see what happens. I am only afraid that it will fry the
>swittch though. If it does.. oh well.. here goes $65 and the Q is out of
>commission until I get a new one. 
>
I took mine apart - a small screwdriver will pop the epoxy and the top of
the cover comes off. Inside is an arm connected to the throttle, with a cam
attached to it. The cam rotates with the arm and actuates contacts at
greater than 57 degrees throttle position for WOT direction to your ECU. The
arm comes down and actuates a microswitch that operates your decel valve.
This opens the bypass valve around your sensor plate, allowing it to fall
until 1200 rpm. Then the valve closes (ECU direction), allowing the sensor
plate to slowly come to a rest position. When the system operates correctly,
you'll see RPM fall quickly untill 1200 RPM, then slowly drop to correct
(825) idle speed. Your main problem is the microswitch is either acting up,
or the arm is slightly out of adjustment. If you feel adventurous, take it
apart and play with it. If you need a new microswitch, I have on sitting
here on my desk I'll send to you (perks of a second job at repairing video
games...). It has to be soldered in. Some people have reported that on
checking this they found bad solder connections - touched them up with an
iron and all was well. My advice is play with it first. Almost impossible to
screw up, and you can always blow the 65.00 later... Now you know more than
you ever wanted to...

>Oh and if anybody has the directions to replacing the temperature sending unit
>(the one under the upper radiator hose) please send them to me. I need to
>replace the unit sometime this week. Thanks alot!
>

I unplug it and use a big crescent wrench. Takes 5 minutes max, unless you
want more excitement, then try doing it hot... Pls kids, don't try this at home!

********************************AUDI FAN***********************************
                                       EMCM(SW) Dave Head  
87 5KCSTQ 176K miles and counting... 1.9 bar boost - Whee!
                                              Maitland, Florida
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