Q: Service stabitrak traction off check engine light flashing on an 07 avalanche changed plugs wires and throttle body tb sensor

The traction control malfunction may not be related to the engine malfunction(s). In any event, the engine issue should be resolved first, especially as you have misfiring which has the potential to cause follow-on damage to other vehicle components (catalytic converter, for instance). There are many, many causes of misfiring and, in the absence of an actual diagnostic, no one of these causes is any more likely than the other to be the actual cause of your misfiring. Diagnostic Trouble Code P0300 can set if you have faulty spark plugs, low compression, damage or excessive wear of spark plug wires and/or coils, faulty fuel injectors, clogged EGR valves or tubes, burned valves, improper ignition timing, vacuum leaks, leaking head gasket, faulty camshaft sensor, faulty crankshaft sensor, faulty mass air flow sensor, faulty oxygen sensor, faulty throttle position sensor, faulty catalytic converter, and others. If you want the cause of the misfiring pinpointed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a misfiring diagnostic and the responding certified mechanic will get this diagnosed and resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.