The other "Regulars" may have more Technical Info,
But if you are still running the OEM Hatachi Carb. , it is best if you leave everything connected.
The ECM collects data from all that "CRAP" to run the carb.
Now if you want to up-grade to a Weber Carb replacement, you can "Shit Can" most of it, including the ECM.
Save the PCV valve set up.
The Weber Carb made for the 1.3 8V is GREAT, just don't expect 100 HP in a box!
Also, if you elect to go the new carb route, send me a PM and I give you some EZ Tuning Tricks
to get a little more Zip in your Doo-Da.
CAPT