Date:         Thu, 10 Jun 2004 11:58:50 -0700
Reply-To:     Craig Oda <craigoda@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Craig Oda <craigoda@GMAIL.COM>
Subject:      Re: Fuel system...follow up
Comments: To: rdawson@uoguelph.ca
In-Reply-To:  <40C868B9.7010106@bellsouth.net>
Content-Type: text/plain; charset=US-ASCII

Ryan, I did the fuel/air mixture adjustment that John Rodgers referred
to.  I am a mechanical novice and had mixed results.   Your experience
may vary.  I think the first place to start is to look for exhaust
leaks before the O2 sensor.  If you want to adjust the air/fuel
mixture, be aware that you could mess it up and it's generally not
recommended to play around with it sense home mechanics generally
don't have access to proper tools to test emissions.

If you play around with the fuel air mixture, you'll need a digital
voltmeter.  These are cool little toys anyway and maybe you already
got one.  If you don't, then you need to consider the cost of the
voltmeter.

First, you need to get the sensor hot.  So, you need to run your
engine until it reaches operating temp.  Maybe drive it on the freeway
or something.  The exhaust gets hot, so don't burn yourself.

Connect the O2 sensor wire to the digital voltmeter.  It's going to be
moving up and down, but you want it to be at .45 volts, or 450
millivolts.  If it is hovering around 600 millivolts, then the O2
sensor is telling you that it the vehicle is running rich.

Now, for the part you may not want to do.  You can adjust the air/fuel
mixture by turning a screw on the AFM.  It may have a dust cap on it.
This is small and round.  You don't need to open up the AFM unit
itself.  You can tighten and loosen the screw and you should see
voltage changes.  Try to get it to hover around 450 millivolts.

If you can't adjust your screw because it is all the way out, you can
tighten the spring by moving a ratchet wheel inside the AFM unit.
Now, possibly like me, you're really starting to screw up your
air/fuel settings.  So, remember how many clicks you tighten the
spring.

 Or, maybe you're on the path toward getting the old waterboxer
humming.  Remember my own engine is kind of misfiring.

-- Craig




On Thu, 10 Jun 2004 08:57:13 -0500, John Rodgers
<jh_rodgers@bellsouth.net> wrote:
> What year is your vehicle?
>
> If you are running a 2.1L WBX, then you may be having a problem with the
> O2 sensor, or the Temp II sensor. I recall reading on this list a test
> for the O2 sensor voltges using a meter. If they are off, then the ECU
> will go to "Rich" for the fuel injection. I don't know where to tell you
> to find the info. Maybe another list memmer can. I think the procedure
> is posted on a web site somewhere. I think the Temp ll sensor also
> affects how rich the mixture is.
>
> One other thing. Set your idle speed correctly. Warm the engine, shut it
> off, disconnect the Idle Stabilizer Valve, Start the engine, turn the
> big flat common screw by the AFM right or left until the idle is 800-900
> rpm, then stop engine and reconnect the ISV. Allow to get cold for a
> cold start. Start engine, ISV should kick up rpm to 1000-1200 rpm and
> then drop back to 8-900 rpm as engine warms.
>
> Hope this helps just a bit.
>
> Regards,
>
> John Rodgers
> 88 DL Driver
>
>
>
> Ryan Dawson wrote:
>
> >Hi everyone,
> >
> >Well, I thought that I had made the neccesary repairs and replacements to my
> >fuel mileage problem.  Below is a list of the adjustments that I have made:
> >
> >1. new fuel injectors (manufacturer - Echlin)
> >2. new air filter
> >3. new spark plugs (platinum)
> >4. new oil and filter
> >
> >There are no leaks in the system, as far as I can tell.  The problem is, I
> >installed the spark plugs yesterday evening, and then drove about 5 miles, and
> >when I came back I realized that I forgot to check the gap spacing on them.
> >So, I took the plugs back out, and they were BLACK again!  I'm going on a
> >camping trip today and am hoping to get better fuel mileage than a Hummer!
> >Does anyone have any ideas?  Could it be that they are dirty due to the
> >previous incomplete combustion?
> >
> >Any thoughts or theories are welcome!
> >
> >Thanks in advance,
> >Ryan
> >
> >
> >
>