I have a 99 S80 T6 and recently it has developed a problem with the engine. It started one day as i took a turn and started to accelerate out of the turn, I accelerated too hard, and the STC kicked in. After i could accelerate again, the check engine light was blinking and now any time I press on the gas the light starts to blink, and the engine vibrates and doesnt accelerate as fast as usual, any suggestions

 

The car is misfiring.
Either spark plugs are bad or the coils are bad.