Hi guys, I have been having an issue with my focus st 2009.
When I drive the car fast ie over 5000rpm then the engine management light flashes and the car starts to misfire. But if I pull over and switch the engine off and start it again the problem is gone. I have also check fault codes with bluefin which says no dtc found. It doesn't do it all the time only twice this year. I fitted rs plug thinking it was spark blowout but still no change. Ps the car is at stage 3.

Thanks!