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Subject:Re: Digijet Idle Problems
From:Michael Diehr
Date:Tue, 12 Aug 2008 15:20:45 -0700

hooked up my timing light and played with the AFM idle CO bypass
adjuster screw -- it was about 1/2 turn open from the fully screwed in
position.   at the fully screwed in (fully closed? i'm guessing) the
idle was slightly smoother.

I then played with the big throttle idle air bypass screw:  I was
doing this with the idle stabilizer in circuit, and it was interesting
-- I could see the timing jumping around as the stabilizer functioned.

Idle air screw too far closed: timing was advanced about 10-15 degrees
almost 100% of the time, engine RPMS sagging below 850
Idle air screw a little too far open: timing went back to 5BTDC and
stayed there, RPMS 850
Idle air screw way too far open: timing went back to 5BTDC and stayed
there, until the engine RPMs ran up to 1200 or so at which time the
timing advanced (presumably the distributor was advancing it).

So, my new question is : is there a way to adjust the idle air bypass
by watching the timing?  Presumably, if the air bypass is "just right"
one would expect to see the timing bouncing around a little bit, but
mainly staying at the stock setting...?

On Aug 12, 2008, at 2:49 PM, Jim Arnott wrote:

> Change the idle stabilizer. Little green box with two round plugs on
> the
> bottom just in front of the coil on the l/h side of the engine
> compartment.
> That would be my *guess*
>
> Jim
>
> ----- Original Message -----
> From: "Michael Diehr" <md03@XOCHI.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Tuesday, August 12, 2008 1:46 PM
> Subject: Digijet Idle Problems
>
>
>> The engine runs smooth and with good power, but idles like cr*p --
>> seems like it's missing and has a slow-fast-slow-fast pattern, even
>> when it's holding steady near 850rpm.