Q: Car misses under load

Hi there. A miss under load indicates a secondary ignition problem. Your ignition system is divided into two components: the primary and secondary. The primary side of the system includes low voltage items including the battery, ignition switch, control module, crankshaft sensor and primary coil windings. The secondary side of the system includes the secondary coil windings, spark plug wires and spark plugs. The control module interrupts current flow through the primary windings of the coil to create the high voltage needed to fire the spark plugs. A problem with the plugs, wires or coil pack will produce a misfire under load and store a diagnostic trouble code in the control module’s memory. A trained technician will use this code as a starting point to diagnose your vehicle. I suggest you have the team at YourMechanic properly fix your vehicle.