ECU remains on intermittently

[1uzfevolvo]

Finally have a starting and running motor and have been playing with the tune.

One of the things that occasionally pops its head up is that when I turn the key off, the ecu and motor continue to run for maybe a second or two. This strange issue has been there since I first got the motor running 6 months ago and it still remains an intermittent thing through changes to the firmware, tunes, temperatures and even the amount of time/miles the motor has been running. Everything else turns off like radio and heater fan so I'm a bit lost.

It doesn't appear to cause any other issues but it is one I'd like to address. Anyone experienced similar or have a suggestion of what might cause it???

[jsmcortina]

Possibly a backfeed from the alternator charge wire? Try temporarily disconnecting the wire to the dash alternator light and see if it continues.

On some installs I have needed to install a 1N4001 diode with banded end towards alternator in that wire. Some BMWs install it in their factory wiring.

James

[ashford]

do you happen to have one of the iac outputs running a relay?

[1uzfevolvo]

Thanks for replys.

Feed back from alternator is something I can look at. Wouldn't this be a problem all the time?

As for the IAC, the MS3 wires are direct.