all depends on weight and how you get in. leather isnt scratch resistant lol. look at a leather wallet. even going in and out of the back pocket it wears down and thats not even putting weight on it while sliding into your pocket
Did you unplug or plug any module while battery was connected? If so may have bricked any one of them. But a scan tool should be able to still connect thru obd port and tell you which module isnāt communicating. If not start testing the obd port continuity
if theres oil there thats usually coming from the valve cover gasket/lube seals leaking in š¬
the porcelain for #1 looks like it has more black soot than the rest. usually from running richer than the other cylinders
ok.... so him telling you to get fueling upgrades and flex fuel kit is good advice for your use? you wont even be using E so whats the point of all the extra items. just adding more fail points. but you do you boo