Spark signal generation

[Scot A. Sealander]

Dave Zug wrote:
 
> to get my ECM to run on a bench, i think i read that some sort of
> feedback spark reference is needed to simulate a "running" engine, in
> addition to, of coarse, key sensors attatched, or POTs. can someone
> explain what is basically needed and how it can be simulated?

It depends on what you want to do.  The C3's will accept a 5 v square 
wave at the distributor reference input and accept it as engine running.
I don't remember the last P4 I looked at...  I do remember that the P4 
would not accept the 5V square wave as the VSS input.

 
> you should see the image in my head of my test bench! the wife is gonna
> freak! who has the best " i thought she was gonna kill me when i ..."
> story? (20 words or less, and limit it to EFI)  :-)

Ah, been there, done that, am still living....  That is only 8 words! I 
think most of the wrath came from spending so much time in junkyards 
looking for all those ECMs. ;-)  And then bringing all that junk home. 
(Our five year old twin girls did enjoy unwrapping all the black tape 
from some of the harnesses.)

To make ECM interface easier, I hacked out the ECM portion of the wiring 
harness at one of those U-Pull-It places.  I think it cost 5 bucks...
An aluminum bud box and a bunch of binding posts now make ECM bench 
connections real easy.  It will save you time if you do this.  It is 
about 20-25 dollars for the bud box, a lot more for the binding posts.


 
> oh,
> wanted:
> 
> 1) "pathfinder II" cartridge for OTC 2000 scan tool. (89 P4-MAP).
>         sell me one or offer a lead to one please. 
Maybe a custom built scan tool. ;-)


 
> 2) an eprom burner that'll do 27c256's. work took my toys back.

I bought "The Pocket Programmer" from Intronics, Inc. in Edwardsville, 
KS.  It connects to the printer port, so it works easily with the laptop.
That was only 129 dollars.

 
> 3) all of GM's source code, and a code calibrator hog tied and         
> delivered to MD, USA.

Tall order! Can't help there.


Scot Sealander   Sealand at clarityconnect.com