Date: Wed, 1 Jun 2011 09:59:03 -0700
Reply-To: HotelWestfalia <zolo@FOXINTERNET.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: HotelWestfalia <zolo@FOXINTERNET.NET>
Subject: Re: Failed emission test
In-Reply-To: <20110601154730.GA89336@tenma.swcp.com>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Check the idle switch operation. It has to switch off when you release the
gas pedal. It can be sticky or only working sometimes. This switch tells
the computer that you are in idle mode, and thus sends fuel accordingly.
Also the idle can be adjusted by the big headed screw on the throttle valve.
Not likely that your AFM is at fault. But check all your little vacuum
lines and change the weak ones.
Zoltan
----- Original Message -----
From: "William" <grateful@SWCP.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, June 01, 2011 8:47 AM
Subject: Failed emission test
> After all the years being on this list as a lurker, I have a minor
> problem with my 1984 Vanagon.
>
> I failed the first emission test because the idle RPM was above
> 1200 during the idle test. The HC reading was only 56 and the
> CO was only .24 during the high RPM test. So I do not suspect
> engine wear as the culprit. Also the engine was completely
> rebuilt in 1998 and I have put less than 50K miles on it.
>
> This happened a few years ago and the problem disappeared after I
> replaced the O2 and temperature sensor(not the dash sender).
> So I replaced the O2 and temperature sensor yesterday.
>
> This time, the idle RPM improved but was still flaky. After
> the high RPM test (2500), the idle RPM remained too high until
> the accelerator was bumped. And then the idle would slowly creep up
> but not above 1200. The emission test equipment was not happy when
> the accelerator was momentarily bumped and it aborted the test.
>
> Now I suspect the AFM. Many years ago(15) I had idle problems
> and the mechanic determined the spring in the AFM was worn. He somehow
> tensioned the spring so the spring applied more force. This fixed the
> problem until I replaced the AFM.
>
> I am sure this problem and solution is in the Vanagon archive but
> I honestly have never needed to search it. I do not even know
> where the archive is located.
>
> If some kind person would direct me to the archive, I would be
> very grateful.
>
> Also, the Vanagon mechanic retired at Hans Wittler's Automotive and
> now they do not service Vanagons. Anyone in ABQ know of a good
> Vanagon mechanic?
>
> Thanks!
>
> --
> William
> grateful@swcp.com
>
> 505 440 0760
>
> Too many people spend money they haven't earned, to buy things they
> don't want, to impress people they don't like.
> -Will Rogers
>
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