So my dad has a titanium fiesta 1.0 100hp. Soon after the purchase he got a remap...went to 140hp. All's well and he is happy with his new ride. A month ago he decided to install a custom made catback exhaust...soon after that i logged it in the obd to find that out it read possible detonations a.k.a knocking... we changed gas station, hoping it would be from poor gas, but the problem remained... went to the garage and the guy there used some kind of headphone to listen to the motor and spot the "possible detonations", but heard nothing! The car was purring like a cat even at the rev limit. Problem is the car still reads knock retards, thus affecting its performance...

all in all we concluded that the catback might be to blame due to the extra back-pressure it applies to the car. So we change the flexi pipe which is the main reason to cause knock retards in an exhaust...well surprise surprise... torque reads less "possible detonations" but still reads some...

I may have tired you with the long post... but i hope you understood what i have written. Any thoughts?

having knock is not good, i would avoid thrashing it until you solve the issue, or you may do expensive engine damage, does your reader measure how much knock? and at what revs/load,

what map is the car running? bluefin? if so revert back to 100hp and recheck incase the exhaust is causing excess vibration making knock sensor think its engine detonation retarding timing and throwing extra fuel in to combat