Q: Blinking check engine loud noise loss of acceleration

If your vehicle’s check engine light is flashing, that means there is a serious fault, usually cylinder misfiring, that requires immediate repair. Misfiring, in particular, has the potential to damage the catalytic converter which can result in additional costly repairs. Misfiring can be caused by 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 other causes. 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. The diagnostic and repairs would also include the trouble code that you have referred to, namely P0420, which code may be relevant to your car’s malfunction. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.