Aldl Communication Again

[Dave Zug]

I saw something like this with a diacom I used for a bit...

my website (under the buick GN section) has a link to pictures of the graphs
during this glitch - high load, high RPM, it just goes berzerk - and the car
goes into 31 degrees retard!  It does cause I felt the power loss big time.

I learned not to trounce the throttle when it would normally shift up to
first gear, thats when it happened. I pulled back low load timing (had to do
with cam change) to fix it, it worked somewhat - i thought the 47 degree
timing was firing the charge too close to the intake valve still being open.
higher octane helped it not to happen also.  I thought maybe super-severe
knock was causing electrical noise maybe.  the problem faded, and I stopped
driving it so hard but never really found an answer..

heres the link to the scan data graphs (concatonated using a paint package -
no its no custom utility)
http://www.delanet.com/~tgp/gn/noyz.jpg  the time spacing is about 1.2
seconds per click.


----- Original Message -----
From: Richard Wakeling <kojab at ar.com.au>
To: <gmecm at efi332.eng.ohio-state.edu>; <diy_efi at efi332.eng.ohio-state.edu>
Sent: Tuesday, November 23, 1999 2:10 PM
Subject: Aldl Communication Again


> Hi all again,
>
> I'm still stuck on my previous problem so if anybody's got any more
> hints that would be great.
>
> Another problem with Aldl comms. I'm getting interference from the spark
> leads I think. When my car cranks or goes into high load in high rpms,
> my data logging devices goes a little haywire and some readings goes
> high or low, like little peaks/spikes. Its really annoying and it upsets
> all my calcuations. How does Diacom get over this problem? Should I be
> using a ferrite rod or something to filter the spikes out? Should I even
> build a circuit just to filter out the noise?
>
> Any help would be greatly appreciated.
>
> Andrew Wakeling.
>
>