Date: Mon, 5 Feb 2001 15:39:52 -0700
Reply-To: Jon B Kanas <kanas@QUALITY.QADAS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jon B Kanas <kanas@QUALITY.QADAS.COM>
Subject: Bride of RapidIdle
Content-Type: text/plain; charset="us-ascii"
Hi Keith and Listers,
Awhile back I posted to the list regarding my 1987 Syncro's desire to idle at 2000 rpm when warm. List response and own diagnostics pointed to a failed tempII sensor. Sensor inexpensive and replace next warm opportunity; also checked idle switch on throttle body and pulled and cleaned idle air solenoid valve. All connections clean and all items operating as expected, including but not limited to 20yr old Radio Shack multimeter. Problem solved..... until last Friday.
Discovered through trial-and-error that disconnect / reconnect of idle air solenoid will return idle to normal, and I can't get it to duplicate the fast idle for awhile; then, as if by magic, it starts idling at 2000 again. When first releasing the throttle, like when you shift, the idle drops to 950, then returns to 2000 within a few seconds. Anytime the problem surfaces, the disconnect / reconnect of the solenoid will resolve it. Shutting the Vanagon off, then restarting it does NOT!!! This is weird. I can find no relationship between temperature, operation, weather, engine load or phase of moon which explains this.
Local shop said there is a module (idle motor controller) in the engine compartment which triggers the solenoid (which he calls the idle motor). He said he recently replaced one at $200+!! Any of you listers out there have any experiences you'd be willing to share:
What tells the idle air solenoid to open?
Is there a relay which is related to this system which could be sticking? The solenoid seems to draw a lot of current to be controlled by electronics alone.
What is, and where is, the idle motor controller? Any experiences with this module would be appreciated?
Regards to all,
Jon B Kanas
Longmont, Colorado
Cultural Center of the Universe
303-678-0658
kanas@qadas.com
Date: Mon, 5 Feb 2001 11:03:01 -0700
From: Keith Adams <keith_adams@TRANSCANADA.COM>
Subject: Re: Rapid Idle when Warm / Throttle idle switch
Jon (& list),
We've been having rather warm weather lately, and after road
tripping to Seattle, where due to warm dense air, my idle
increased to 3000 rpm, I figured it's time to do something.
I replaced the Temp II sensor. Surprisingly, I bought it at
the local VW dealer, and it costs $12.05 CDN after a 20%
discount (VW Club). Pretty good considering the BD or
Vanagain is $9.95 USD! And the dealer had one in stock.
The surprises never end.
I replaced the sensor, and lost the usual cup of coolant or
so. However, that didn't do the trick. Still idling high.
(I'm glad it wasn't an expensive part!). Next thing? What
next? Well, lots of people said check the throttle position
swtich. I turned it, heard no clicking. However, not sure
how loud the click should be. So I popped the air cleaner
off, took the AFM out and the rubber boot and took the
throttle body off. Grimy is an understatement. Took it in
the house, laid it on the table and proudly exclaimed to my
bride to be "Will you look at the gunk on that thing". I
was quickly scuttled into the basement.
I cleaned the throttle body up and got the gunk off the
switch. Still didn't seem to click. Realize I don't have a
multimeter. Go to Radio Shack. Buy multimeter. Come
home. Return to Radio Shack with defective multimeter.
Spend 20 minutes in RS trying to find a multimeter that
works. Find one. Determine switch ain't switching. Stuck
in the open position. Try cleaning some more and working
the switch. No good. Remove switch from backing and play
with it more. No go. Either at idle or WOT, although it
had been switching at WOT prior to cleaning.
So I popped the cover off the switch with an exacto knife.
Cleaned the contacts, and re-bent the bracket for the spring
and the switch works again. Re-glue cover of switch,
re-assemble whole ordeal, works fine. Put it back in the
van, and drive around for a bit to get it warm (since
condition only occurred when warm). Still happens - 2200
rpm idle. So pull back into my parking stall (now dark as
the inside of a cow out). I adjusted the switch with the
eccentric as far as it will go, and it works - sort of. It
now only works if the throttle really snaps back. But my
idle resumes normalness. I suspect there's just enough play
in the system to stop it from fully activating the switch.
So it's OK. When I drive, if I come to a stop and it's
idling, I just have to give the throttle a quick stab to get
it to snap back. My concern is that when I'm coasting it's
not going to do that. I may add another spring to help the
throttle return more firmly.
Anyone on the list with advice on how to get the throttle to
return fully and engage the switch? I've maxed out the
adjustment on the switch (with the eccentric). I don't want
to touch the screw that BEntly says not to touch, but is
that a good way of adjusting that or not? Is a second
spring a good/bad/dumb idea?
Keith Adams
Calgary, Alberta, Canada
1986 Vanagon GL Westfalia
