Stupid ignition quark with 90 - 91 PM6..
 

Ok, here's the skinny.. engine won't turn off when the key is removed. Keeps running as if the key were there, and in ignition on..

1991 Civic Hatchback DX.. MPFI swap from 1991 PM5 to 1988 (CRX) PM6.. everything works fine, engine shuts off..

Modified ("chipped") 1990 PM6 in place of 1988 PM6.. engine wn't shut off.. Thought I messed up the desoldering or dripped some solder or something..

Obtained another 1991 PM6.. unmodified, tested while unmodified, engine won't shut off.. Put back original PM6 (1988 CRX) to test to see if something was shorted.. engine shuts off fine.

Obtained one more 1991 PM6, tested unmodified, engine won't shut off, test modified ("chipped"), engine won't shut off.. test original 1988 CRX PM6.. engine shut off fine.

WTF?! ???

Re:Stupid ignition quark with 90 - 91 PM6..
 

my only guess right now is that the 88-89 ecu's have a different pin out. Check some manuals and see if the pin outs are the same or different.

Other then that, try some other 88 pm6's

Re:Stupid ignition quark with 90 - 91 PM6..
 

All information I have found state the pinouts for the PM6s are the same, straight across the board. Which is what is soooo weird. I've been dealing with this issue for about 2 months or so now, it's obnoxious.

But what sucks is, I need the '90-91 for it's easy ability to "chip". Oh well..