02 wrx small evap leak and all 4 misfires

What about the misfires does it pull smooth? the misfires can be per 100 revolutions of the crank what are the codes "generic" or a real scan tool are you reading the Data in real time? these issues shouldn't take to long to locate. Car seems very close to stock have you checked fuel trims?

P0300 SUBARU - Random Cylinder Misfire Detected.... Possible causes - Faulty spark plug (s) - Faulty ignition coil (s) - Clogged or faulty fuel injector (s) - Intake air leak - Fuel injectors harness is open or shorted - Fuel Injectors circuit poor electrical connection - Ignition coils harness is open or shorted - Ignition coils circuit poor electrical connection - Insufficient cylinders compression - Incorrect fuel pressure... The P0300 code means that a cylinder(s) is misfiring or is randomly misfiring. Start by checking for intake leaks, intake gaskets are common caused of multi-cylinder misfiring. If no leak are found the next step is to replace the spark plugs. If the problem persist more tests needs to be done to diagnose problem,............................P0442 SUBARU - Evaporative Emission Control System Malfunction... Possible causes - Missing or loose fuel cap - Incorrect fuel filler cap used - Fuel filler cap remains open or fails to close - Foreign matter caught in fuel filler cap - EVAP canister or fuel tank leaks - EVAP system hose leaking - Fuel tank leaking... The P0442 code means that the control module has detected a small leak in the Evaporative Emission (EVAP). Loose fuel tank filler cap is the most common cause that triggers the P0442 code.

i used to get misfire codes all the time, about 2-3 hours of driving would turn on cel after resetting. i changed from a lightened flywheel back to a stock flywheel and now havent got the code again in sevral thousand miles..