Racers Group

[geo3@earthlink.net]

Probe Dude <probedude@hotmail.com> wrote:

>Piggyback does not necessarily mean "take over functions of the ECU".
>What piggyback systems do is modify the values read from all the sensors
>under the hood to fool the ECU into generating a different spark curve,
>injector pulse width, etc.

I am aware of that.

What you apparently aren't aware of is that this screws with the ECU's learn
and adapt (or however you want to describe it) programing.  Nissan ECUs hate
piggybacks for this reason.  I can't give you the deep technical background on
it, but this is what happens.  The ECU tries to adjust for the altered signal.
This makes the piggy alter the signal again, making the ECU alter again and so
on and so on.

Most people who use them have a horrible time with them.  I know they work OK
with other brand ECUs.  The DSM folks seem to like them.

George Roffe

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