Date:         Wed, 13 Jun 2012 03:23:25 -0400
Reply-To:     tinkerman007@GMAIL.COM
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         tinkerman007@GMAIL.COM
Subject:      Re: Any way to trick the Digijet ECU into generating injection
              pulses without the RPM/ignition signal, for test bench purposes?
Comments: To: Scott Daniel <scottdaniel@TURBOVANS.COM>

On Sat, 2 Jun 2012 12:00:39 -0700, Scott Daniel - Turbovans
<scottdaniel@TURBOVANS.COM> wrote:

>> Does anyone know if activating the start signal causes the ECU to
>> output injection pulses regardless of the RPM signal?
>
>I can't imagine that it would. There is a 'start signal' input to the
>ecu , but for that  to  cause the injectors to get triggered without
>also knowing that the engine is turning - that really would seem 'not
>right' at all.
>   Sometimes people crank on the starter for a minute steadily.  That
>just could not work.

Yep, I completely agree with that but take note that I was talking about
"tricking" the ECU on a test bench, not in a real van with real injectors
and gasoline...
Anyway, I've managed to get to injection pulses by injecting artificial
pulses into the HALL sender/RPM input.

>of course..if hydro-locked with gas..just remove the spark plugs to clear
> the fuel out,

That's more work and not so convenient where I was and without tools, so I
just cranked till it got free...my guess is that no harm was done because
there's also compressible air in the cylinders, not just uncompressible
gasoline.

> Crank it on starter with a remote starter switch with fuel and ignition
> systems not on.

How do you install a remote starter switch? Do you connect it directly to
the starter solenoid?

>I had an ECU do exactly this in a 1.9 wbxr ...injectors on all the time,
>as soon as you turn on the key.
>I sent that ecu to David B. to look at ..
>basically we decided it was junk I think.  He may still have it.

From my experience, in this scenario the ECU's main processor is dead. And
it's not easy to replace the 40 pin chip (let alone get hold of one...).