MSefi.com read only forum (Jan.15,2018)

A good 95% of the time a have a Preignition Knock at start up on a warm engine. It occurs only at the transition from crank to run. I can see the resulted RPM and Ignition timing drop in the attached MSLs. I have attached two MSLs and one MSQ. MSL 5.1 121109 has the cranking trigger set to trigger rise (still knocks). MSL 5.1 calculated 121209 has the cranking trigger set to calculated which also gives a knock at the crank to run transition. I have researched what I can to solve this problem - any guidance/recommendations?

You can try decreasing table spark advance in the rpm, map region where the knock occurs. You could also try richening the after start enrichment.