Hi All

Had my Focus ST for 4 months and loving every minute of it but wondering if I am doing something wrong as over the last few weeks the engine fault acceleration reduced warning comes up on the dash, Showing no codes or history of codes on a MAC fault finder which isnt helping and I dont have £100 for Ford to take a look this month. Could it be because i have not used super unleaded for a while? I used to switch between both but not for the last 5-6 weeks so much. Any ideas?

Thank you