2015 Mitsubishi Mirage 112,000 miles automatic: Car jerks when starting out.

Hello, it's tricky because the "jerking" could be representing more than one possible problem. First, you could have a transmission engagement issue. This could cause jerking on engagement at slow speeds, and also the thing where the engine speed rose and required hitting the brake to stop it. Second, you could have an engine performance issue. Engine performance, such as ignition, fuel or air intake concerns, or even emissions controls concern. If you replaced the spark plugs, you may need to replace the coils as well, as they could cause misfire and jerking if removed and reinstalled. Seek local guidance at a shop near you for further testing and advice. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops