Hey Mike.

If one side really is leaner than the other it will be because it's getting
some extra air somewhere, like a leak.

Considering the hokey nature of the intake plenum/runners it wouldn't
surprise me. Try spraying something lightly combustible, like WD-40,  on all
the joins and connections while its running and listen for an RPM increase.

On 9/16/07, Geza Polony <gezapolony@sbcglobal.net> wrote:
>
> Mike (Eliot),
>
> Do you KNOW the two cylinders are running lean/rich, or are you just
> looking
> at the plugs and surmising? There are a ton of things besides the mixture
> that can make plugs look whiter in one or more cylinders, eg., certain oil
> additives, a water leak into the cylinder, etc. NGK has a site with
> pictures
> that gives a good clue as to what the plug appearances actually mean. I'll
> see if I can relocate it.  Any way you could post pics of the plugs?
>
> Your O2 sensor isn't the problem. There's no way it could make only two
> cylinders run leaner or richer. I don't see how any other central fuel
> delivery component such as the FP regulator or pump could cause two
> cylinders to run lean/rich, either. These provide equal pressure and flow
> to
> all injectors, even when they're faulty. They don't choose.
>
> Have you done the Bentley "ECU pin test"? Since it's free, that would be a
> good place to start in chasing down your problem. If the resistance in two
> injectors is markedly different from that of the other two, it might
> indicate a problem along the lines of what you're talking about.
>
> If you've recently run any oil additives, change your plugs and drive a
> hundred miles, then reexamine. If you're losing any coolant at all, and
> the
> plugs on one side are whitish, that could explain where the coolant is
> going.
>
> Geza
>

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