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Subject:Re: [WetWesties] Air Cooled 2.0 : High Hydrocarbon (smog) Parts Check?
From:neil n
Date:Wed, 27 Feb 2013 14:54:40 -0800

Bradon et al, much thanks.

I had read of the brake booster affect on engine but wasn't clear on the
relationship until I saw the van.

The vacuum hose to the aux. air valve is capped as is a hose at "T" at
brake booster vacuum pipe. I assume the aux. air valve vacuum hose connects
there. I pumped the brake pedal. It had no affect on idle.

Good tip on cat. Did not know that! Another use for pocket IR gun! And I
assumed the cold start "5th injector" ran til engine warmed up. I recall
now how it works (i.e. some wire in a switch to operate valve manually
during cold start)

This van is in rough shape. I didn't bother test driving it. More here if
you're super bored:

http://www.thesamba.com/vw/forum/viewtopic.php?t=546310

Neil who had to go get sandpaper anyhow.    ;^)

On Wed, Feb 27, 2013 at 2:31 PM, Brandon <brandon314@gmail.com> wrote:

Neil,
>
> The cat, after extended driving/usage (even revving to 2K or so for an
> extended period without load) should be hotter on the outlet than on the
> inlet. This is easiest to find with temperature probe (sometimes a good IR
> one will work).
>
> A cat, non-functioning, will show same temp across both (or a drop).
> Plugged catalytic converters are less common on VW but usually affect
> engine power to the point that the vehicle is difficult to drive.
>
> The usual culprits (vacuum leaks, exhaust system holes, etc.) are all
> worth checking. Pumping the brakes a few times should cause the engine RPM
> to slightly raise, not drop, if the mixture is properly adjusted.
>
> Cold start valve (and associated Thermo Time Switch) are not worth
> worrying about (outside of possible leaks) because they only activate when
> the key is cranking.
>
> L-Jet is pretty simple but not the most refined fuel injection....so don't
> expect miracles :-) It should pass if the vehicle is a strong runner though
> (non-blown engine).
>
> Take care,
>
> Brandon Math,
> KD7INF
> brandon314@gmail.com
>
>
>
> --
Neil n

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'88 Slate Blue Westy to be named.

'81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/

Vanagon VAG Gas I4/VR Swap Google Group:

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