Re: 5KT : Intermittent high idle

[John Karasaki <johkar@teleport.com>]

At 07:46 AM 4/14/97 -0700, you wrote:
>
>	For the past few weeks, my '85 5KT (142K) has been exhibiting
>	intermittent high idle (~1100 -1200 rpm), <
<snip>
>
>	Recent repair history -- new ISV, a couple of new hoses, 3
>	new injectors (which fixed a nasty power-loss problem). No
>	obvious vacuum leaks, but the boost gauge has been reading
>	0.8 bar at idle after these repairs.

<snip>

I and others have mentioned this before, but here goes:

If anyone on the list with a pre-'91 5000 or 200 has an intermittant idle
speed problem, the FIRST thing to check is the combination idle/full
throttle switch module.  If your car has over 70k miles, it's probably bad.
Every 5kt/q I've encountered with normal mileage has had a bad throttle
switch.  The wagon I just brought home, bad switch...etc. etc.

You can cut them open and touch up the connections with a soldering iron,
but it is a big pain to get them open.  Thanks again to Scott Mockery who
did mine.  I would not have used that kind of force!

Anyway, replacing the ISV fixes the symptom most times and only temporarily.
Check this switch!  BTW, it usually is an intermittant failure.  That is,
you'll check it and it's ok.  Then check it again and it's bad.  If you need
to assume that the ISV or the throttle switch is bad, assume it's the
throttle switch!

Good luck.

Regards,


John Karasaki

Audi Quattro Fanatic