When my 84 went super rich at idle (drowning in fuel) it was because the
fuel pressure was sky high.  Replaced the regulator and all was well again.

On 4/25/07, Dennis Haynes <d23haynes57@hotmail.com> wrote:
>
> The severe cut out with the tach falling to "0" was not fixed by a fuel
> filter. The tach falling is definitely an electrical problem. Either you
> are
> loosing supply voltage or the hall sensor is bad or possibly the ECU.
> Anyway, the ignition pulses also triggers the injectors so this is the
> first
> problem to resolve. Extra intermittent ignition pulses also mean extra
> injection pulses.
>
> Running rich is usually traced back to the o2 sensor system. Bad chassis
> connections at a few critical connections will drive the system crazy. Not
> only do you need to check the connections where the terminals are screwed
> to
> the chassis, but the crimps themselves. New crimp terminals with the built
> in heat shrink can be really helpful. Check the voltage at the O2 sensor.
> Is
> it between .2 and .8? This will tell you a lot. I doubt the AFM is the
> problem. Yes they can cause some acceleration or idle problems, but if the
> system is working, the O2 sensor has the final say.
>
> Dennis
>
>
> >From: Gregor Brandt <gbrandt@MARIONETTE.CA>
> >Reply-To: Gregor Brandt <gbrandt@MARIONETTE.CA>
> >To: vanagon@GERRY.VANAGON.COM
> >Subject: van 'stutters' and runs rich
> >Date: Wed, 25 Apr 2007 23:43:33 -0500
> >
> >'86 Westy
> >
> >I'ved talked about this problem before and tried the suggestions from the
> >list. I have more info and a list of things done.  I suspect I may have
> >more than one thing wrong...but I don't know.  I'm quite frustrated.
> >
> >This started with severe engine cutout...tach would go to 0, then back up
> >to RPM, causing severe bucking.  Hunted and searched and finally found
> >plugged fuel filter...violent bucking went away.
> >
> >Only to be replaced by a gentle stutter when cruising below 3000 RPM or
> >lightly accelerating up to 3000 RPM, after 3000 RPM I do not notice the
> >stutter.  This is not noticeable on the tach.
> >
> >I've tested the O2 sensor - van does same thing, plugged or unplugged.
> >I've removed the Temp2 plug - van runs worse with it off
> >Check timing - ok
> >Fuel filters are both new
> >Distributor cap looks good
> >Hall Sensor getting correct current
> >Jiggling wires does not increase or decrease problem.
> >
> >
> >Could this be the AFM giving me troubles now?   Van also runs very rich,
> >exhaust smells like fuel.
> >
> >Thanks
> >Gregor
>

--
Jake
1984 Vanagon GL
1986 Westy Weekender "Dixie"
www.crescentbeachguitar.com