Re: 5kcsq High Revs during Deceleration

["Mike Hopton" <mike@genesis-microchip.on.ca>]

     Scott,
     Thanks very much. I've ordered a copy of the Bentleys. The good news 
     is they're coming from an ex-list member in Ontario the bad news is 
     the Canadian postal workers go on strike at midnight....
     
     I have been searching the archives and the throttle switches sound 
     like a likely candidate (I think I have a spare one in the basement 
     I'll check tonight). The car surges when I put my foot on the clutch 
     and then let off the throttle, I have to wait a couple of seconds to 
     let the revs drop before engaging the clutch.
     
     Thanks for the tip on the cracked solder joints I'll take a look under 
     the microscope tomorrow. 
     
     This list, and guys like yourself is excatly why I bought a 10 year 
     old Audi as my daily driver!
     
     All the best, regards, Mike
      
Subject: Re: 5kcsq High Revs during Deceleration
Author:  "Scott M." <scottmo@teleport.com> at Internet
Date:    11/13/97 4:45 PM


Mike,

You may want to check the throttle switch, on the 5000T/Q
MC engines these throttle switches are notorious for having
cracked internal solder connections for the idle and WOT
switch. One minute they work great, the next minute they
are open circuit. You can carefully cut off the switch
cover where it is solvent welded to the case and then
resolder the three internal connections near the main
external connector. You need a good magnifying glass or
microscope in order to see the cracked solder joints. Are
you getting a surge/hunting when you let off the throttle?
The Decel valve allows air to bypass the air flow plate
during decel to avoid a rich fuel mixture. The Bentley
outlines the procedure for testing this valve. Some of the
later Decel valves would stick open and cause stalling
after decel.

HTH
Scott M.