The idea of giving a little gas when you start a cold WBX engine (without
dle controller) was from my observations on my ML430 SUV. When I start it
cold the idle speeds up to about 1500 rpm for a couple seconds then going
down gradually to 1200, 1000, 800 and and stops at 550 rpm all in a lapse
of about 30 to 45 seconds. I asked my mechanic about it and he said *"Mercedes
has not used an idle control valve since around 1990. The idle is
controlled by the throttle valve actuator and timing via a sensor... If you
start your cold engine and it idles right away at 550 it will stall and die
and something is wrong with the sensor.**"*

dan

On Tue, Aug 10, 2021 at 4:06 AM Roy Nicholl <RNicholl@nbnet.nb.ca> wrote:

> Jeff:
>
> My son and I did a test week in Fundy (~400km in total) with the ICV
> disconnected.  Occasionally, the WBX stalls at idle - mostly when cold,
> so as Dan said, put your foot in it a little for a minute and all is
> well.  The only other time it stalls is when there is a load on the
> alternator (running lights on) or the helm is hard over (power steering
> pump loaded) at idle ... it does not compensate (I presume the ICU is at
> play ... or asleep ... here).
>
> Fuel consumption may be a little higher typical ... but there could be
> other bits a play there.
>
> Since driving with the ICV unplugged seems to be tampering the wild
> behaviour of the idle control unit, I am going to try waiting until I
> put the Hyena into hibernation to send the ICU off for rebuild.
>
> Roy
>
> Jeff Palmer wrote on 2021.07.27 17:57:
> > Hi Roy. I have had the same issue - surge then idle then surge - for a
> couple of years now. When I drive and not moving it idles nicely at 900.
> Maybe you can wait to send it out until you park it this winter? Assuming
> you don’t drive it right now. Maybe I’ll send mine with you - I’m in St
> Andrew’s NB for holiday. (No van).
> > Jeff
> >
> > Sent from my iPhone
> >
> >> On Jul 27, 2021, at 2:57 PM, Roy Nicholl <RNicholl@nbnet.nb.ca> wrote:
> >>
> >> Stuart:
> >>
> >> That's interesting.  Though being dead-in-the-water for a couple of
> >> weeks or more (I am in Canada) is discouraging.
> >>
> >> Thank-you,
> >>
> >> Roy
> >>
> >>
> >> stuartmacm@gmail.com wrote on 2021.07.27 14:40:
> >>> Idle control unit.  Have it rebuilt:
> https://modulemaster.com/products/vw-volkswagen-vanagon-1986-1991-idle-controller-rebuild
> After 30+ years in a wet environment they all fail.
> >>>
> >>> Stuart
> >>>
> >>> -----Original Message-----
> >>> From: Vanagon Mailing List <vanagon@gerry.vanagon.com> On Behalf Of
> Roy Nicholl
> >>> Sent: Tuesday, July 27, 2021 10:25 AM
> >>> To: vanagon@GERRY.VANAGON.COM
> >>> Subject: Idle gremlins still at play
> >>>
> >>> Good day all,
> >>>
> >>> The Hyena (88 Westy WBX)   started racing at idle (from 1100 climbing
> to
> >>> 2500 last summer).   If you were at the back of the van and pushed the
> throttle hard closed - sometimes wiggling it - the van would fall back into
> an idle.     With the engine shutdown, you had to do the same to hear the
> click of the TPS.
> >>>
> >>> This morning, I replaced the throttle body with a new GoWesty unit.
> Things were fine for the first test run.   After lunch, I restarted the van
> and it began surging at idle, but differently than before.   The WBX will
> surge to 2200 - 2500 RPM, but after 1-2 seconds falls back to idle.   Rinse
> and repeat.
> >>>
> >>> I unplugged the 12v from the idle control valve and the engine
> remained at idle.     I removed the idle control valve; cleaned it with
> carb cleaner and tested it with 12v leads (valve appears to move).   I
> re-installed the valve and the same thing happens.
> >>>
> >>> So, is it possible the spring is too weak and the valve is bad ... or
> is my problem likely to be elsewhere (i.e. idle control unit) and more
> expensive?
> >>>
> >>> What's the impact of running with the power to the idle control valve
> disconnected while I await a new one?
> >>>
> >>> Roy
> >>>
>