Hey I recently installed a grimmspeed lightweight crank pulley and my wrx now seems to have a slight misfire at idle and around 3,000 rpm but seems to run smoother on hard pulls not sure if this is a common problem or not
Plz give advice?
There is a misunderstanding here. The pulley does not actually cause real misfires. It just causes a misinterpretation by the ECU. The car should run no different performance wise. If it is then it is something else.
exactly^
all the lightweight pulley is doing is allowing your crank to rotate easier due to it being lighter of course. if the weight difference is too much, it will just throw a code because it thinks its misfiring when in reality its not