Q: Engine misfire and traction control

Hi There, It is possible that the misfire (depending on how severe) may have produced enough of a jolt in the vehicle to cause the traction control system to detect a change in the stability of the vehicle. The traction control system monitors the steering and stability of the vehicle and engages when loss of traction has been detected. This is done by the use of electronic sensors at each of the four wheels that communicate with the Powertrain Control Module (PCM) regarding steering performance and stability in adverse weather conditions. The traction control system works by reducing engine speed and determining which wheel to apply brake pressure to in order to prevent the vehicle from sliding. The anti-lock braking system and the traction control system work together to maintain the stability of the vehicle. The computer uses this information received from electronic sensors regarding the rotational speed of each wheel, the horizontal motion of the vehicle, and the vertical motion of the vehicle to determine how to direct the traction control system or the anti-lock braking system to best control the vehicle when needed. When this warning indicator light comes on in the dashboard, this could be an indication of several issues such as faulty wheel speed sensors, a faulty steering angle sensor, a faulty rotational speed sensor or a problem with the steering rack. In some cases, the traction control system may simply need to be reprogrammed. In addition, when any of these symptoms are detected, some vehicles may go into limp mode rendering the vehicle unable to accelerate beyond about ~30mph.

Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.