2008 Roush 427R runs great when the car is cold and runs decent when warm in cool temperatures, but after it warms up or air temp gets about 80 or so it spark knocks and hesitates badly and just lacks power from 2000 to 3000 rpm during acceleration. Any ideas? Oh and no codes at all
carbon build up?
how many miles on the car, do you have a Check engine light?
are you running high quality fuel?
had a Mini cooper s in the the shop the other day with similar issues. found she was using 87 octane. 91 is a minimum .
2014 black Mustang5.0 track package, Recaros.
Roush axle back with 4.5 tips /Boss diffuser
Barton twin post shifter bracket
Whiteline adjustable sway bar
Whiteline lower control arm relocation brackets
Whiteline adjustable lower control arms
Airlift Performance air bags
Has 80k on it, never have ran anything lower than 93 octane in it and have tried multiple different gas stations in case may have been bad. Already changed plugs, fuel filter and cleaned fuel injection but still does the same.
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