Date: Wed, 1 Jun 2011 11:33:36 -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: Failed emission test
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Good thought on the throttle cable - there has to be a bit of slack.
and ....really, 'most' of the waterboxer vanagons that I work on have their
throttle switch not making contact at idle. I am constantly adjusting those,
and fixing them when they can't be adjusted.
and I find the timing too advanced on them commonly,
and ...has anyone just turned in the air bypass screw on the throttle body
???
that is the basic idle speed adjustment.
It's *not in the parts* always !!!
It's in the carefully fine tuning, adjustment, and cleaning of things.
there's the mixture screw on the AFM ..but that doesn't need to be fiddled
with very often.
air leaks ....they happen. There can not be *any* air leaks anywhere, from
the AFM to the intake ports. I've found as many as 8 of those, on one
engine.
Someone with some skill, smarts, and experience needs to check things
carefully, and adjust and clean as needed ............and there may be a
part or two not working like they should.
I have improve the running of a vanagon engine significantly, with as
simple a thing as replacing a bad exhaust gasket near an oxygen sensor.
Resist the temptation to think something like that 'can't be it.'
It *all * matters and it all has to be right on these fine silly
waterboxer engines. When it's all right ...they idle right, they go well,
they pass emissions usually, and they get decent fuel mileage.
Now decent is the cat ?
----- Original Message -----
From: "Daryl Christensen" <daryl@AATRANSAXLE.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, June 01, 2011 9:19 AM
Subject: Re: Failed emission test
> Might be as simple as the accelerator cable not releasing to idle quite
> enough when hot. Happened to me recently. Had the cable adjusted a tiny
> bit
> on the tight side, so Backed off it and problem solved.
>
> Daryl of AA Transaxle
> 425-788-4070
> "On the cutting edge of Old technology"
> 86 Syncro Westy w/Turbo Zetec in the trunk
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> William
> Sent: Wednesday, June 01, 2011 8:48 AM
> To: vanagon@GERRY.VANAGON.COM
> 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
| 
