If you aren't in "timing mode" the ignition timing will walk around even at idle. It's a pain but you need to try and get the ecu to go into timing mode. There's a bunch of ways to do it and none ever seem to work consistently lol. There used to be a old website with sr20 set up tricks for getting any stock sr to run great but it seems to be down now. Or the link isn't working for me:
https://www.plmsdevelopments.com/ind...r20-setup-tips