Date:         Fri, 9 Jul 2010 00:23:09 -0700
Reply-To:     Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject:      Re: engine revving at idle
Comments: To: Mark <mbrush@GMAIL.COM>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
              reply-type=original

re
Is it just a matter of adjusting the
throttle valve?

no, you adjust the throttle switch.
On a 2.1 it can be tricky, and sometimes they're stuck in one position, and
sometimes they're just corroded and won't move, and sometimes they'll move
and adjust but won't reach correct adjustment.

it takes a small allen wrench ..
it's loosen a clamp screw, turn an excentric, down in there.

I just discovered a device that totally transcends this mechanical switch ..
and that is a dodgey system after years and millions of miles..
the throttle bodies do wear, plus what I mentioned about the switch above.

there is an electronic replacement. I'l lbe installing one by the end of
july ..
it's a pressure sensor that signals the ecu when idle and WOT are happening
..
and it does it by sensing air pressure, NOT by mechanical position of
something ..
should be 300 % more accurate and consistent, at least.

Scott
www.turbovans.com

----- Original Message -----
From: "Mark" <mbrush@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, July 08, 2010 6:02 PM
Subject: Re: engine revving at idle


> Thanks for all the suggestions - not sure, but I think I found a problem
> with my throttle valve switch.  I followed the test on page 24.59 of the
> Bentley "Throttle valve switch, checking and adjusting."
>
> I get continuity when I start the test, at idle.  Continuity breaks when I
> open the throttle (continuity good at full throttle), but then when I do
> as
> the manual says and "close [the throttle] slowly" - I get no continuity at
> idle again.  I can only get continuity again when I open throttle and let
> it
> snap back into place.
>
> Seems to explain my symptoms since it says "warm engine will have NO fuel
> deceleration shut-off or DLS function at idle" if gap is too small....
>
> but I can't get any continuity when I "slowly" bring back into place
>
> So what now?  How do I fix this?  Is it just a matter of adjusting the
> throttle valve?  Why does it get continuity when it snaps back into place,
> but not when I slowly bring it back?
>
> On Wed, Jul 7, 2010 at 11:36 PM, Mark <mbrush@gmail.com> wrote:
>
>> Has anyone had this problem?  After my engine reaches operating temp and
>> is
>> in stop and go traffic, it doesn't fall back down to idle after I
>> accelerate
>> to move forward in traffic.  It just stays revved at 3,000 rpm or
>> thereabouts.  Not fun when stuck in traffic.  I'm thinking it has
>> something
>> to do with the spring on the throttle (maybe needs to be cleaned or
>> greased?).   I haven't worked on this part of the van yet, so I'm not
>> familiar with how the accelerator cable hooks up and works in the engine
>> compartment.
>>
>> Thanks for any insights!
>>
>> Mark
>>
>> --
>> Mark
>> 1990 Westy (2.1 - manual)
>>
>
>
>
> --
> Mark
> 1990 Westy (2.1 - manual)