Date:         Thu, 21 Jun 2012 20:14:24 -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: CO Adjusting Screw. PO Set it All The Way In? Base Setting?
Comments: To: neil n <musomuso@GMAIL.COM>
In-Reply-To:  <CAB2RwfhA+S2OpCv=qOvTWUW0Rz0WaUpJUTTWpjy0A6LvwXO7aA@mail.gmail.com>
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On 6/21/2012 3:35 PM, neil n wrote:
> When de accelerating, does vacuum created by engine pull the flap on AFM
> open? Even if it does, I imagine wiper movement on the resistive strip
> inside AFM is moot or ignored by ECU during de acceleration fuel shut off
> mode.

Hi Neil.
if you mean 'decelerating' and you are talking about the throttle plate
being closed, I would not expect the AFM flapper to move off it's rest
position in that mode.

seems to me if injector pulse is not being sent to the injectors in fuel
shut off decel mode..
the ecu won't care what the AFM says.  Like not even in the picture in
that situation, seems to me.

I am always 'check the basics'.
I think the symptom is uneven decel and occasional stall instead of
coming to an idle.

Does it idle like a rock ...super steady and consistent ?
if it doesn't ..I'd just work on that.
that may lead to whatever is not acting exactly like it should.

It's just a blockage or leakage of fluids or electrons, or more than one,
and 'fluids' include, vaccum, air, exhaust, etc. not just liquids.

this is how I see it this kind of EFI ..
it 'reads the air' ...
everything about the air flow into the engine has to be pretty right.
I don't especially think some throttle shaft play is that big a deal ..
but I sure wouldn't mind having a better TB on hand to try.

as I said, high miles AFM's are always questionable to me.
I  have like 5 spare ones...
if I'm lucky one of those works pretty smoothly and consistently.

I'd look into the 'air' part a lot, to start with.
I feel better when I know the fuel pressure is right and I have seen the
injectors spray nicely, and not leak.
There are at least 50 things to check .

let us know what you find !
Scott