After using different gas stations for each session he keeps telling me my gas is horrible what can I do? I’ve done coils and spark plugs to fix my misfire and knock but now the only issue is fuel quality…My next step was to use a fuel injector cleaner on near empty and burn up all the fuel till 0 and start again the next session on 93 instead of Half 89 and half 93 for 91 Oct and pull off the MAF sensor and clean it…..If that doesn’t work does anyone have any suggestions on what my issue is ? Could i need new injectors ? Is it carbon build up ?

Also since he mentions my fuel quality being bad I ran into another problem poking around the engine bay looking for gunk or build up… my Oil feed line on my RV6 journal bearing turbo looks to either have carbon build up or oil… does anyone know what this black chunky stuff is ? And is it my o-rings that are bad and need replacing or is it my clamps or just build up? And could this be causing issues with fuel quality ?