The car will start but won't turn over

420 is a catalytic converter problem. causes might be: Damaged muffler or leaks in the muffler Damaged exhaust manifold or leaks in the exhaust manifold Damaged exhaust pipe or exhaust pipe leaks A misfire in the engine Oil contamination in catalytic converter Faulty catalytic converter (most common) Faulty engine coolant temperature sensor Faulty front oxygen sensor Faulty rear oxygen sensor Damaged oxygen sensor wiring Oxygen sensor wiring that is not properly connected Damaged oxygen sensor connectors A fuel injector that is leaking Fuel pressure that is high Use of the wrong kind of fuel (using leaded fuel instead of unleaded fuel) the 299 is a turbo code and you need to have it checked. causes may be: Faulty turbo or supercharger Low oil pressure in the engine Fault in the EGR system Air or intake leak or restriction Faulty boost pressure sensor 456 is an Evaporative Emissions System Small Leak is Detected most common cause of 456 gas cap vent or purge vent valve will not seal completely. 1456 is tank vent valve open which could be valve N80 if gas cap ok 0102 is MAF... is the air filter clean? as for the random misfire and cylinders 2, 3 & 4 misfires, they may be related to the turbo and cat problems. i'd get those fixed and see if the misfires go away.