ecu voltage problem

[Sandy]

A couple of things -

Is the power input to the controler filtered? Are other I/O lines filtered?
Check for ground problems. Is the injector time compensated for battery
voltage, which may not be calculating corectly? 

When you are testing with the powersupply is the Ignition run from that
too? If not, then start looking for noise from that.

Just some good starting points to look at.

Sandy

At 08:32 AM 4/30/97 -0700, you wrote:
>I am an FSAE student and we built an EFI computer for the competition.
>There seems to be a problem running it off the car's power supply, ie the
>battery.  When it is hooked up to the battery the computer holds pulse
>widths at around 1 ms per revoltution regardless of throttle position.
>When we hook it up to the standard voltage regulator used for testing in
>the lab the car works perfectly with full rpm and throttle range, but
>can't move because it is attached to an extension cord.  We're using a
>68hc11 processor.  If anyone has had any weird voltage problems like this
>any help would be appreciated.  Thank you,
>Sean
>
>