Emgrand EC718 automatic transmission jerks during start-up?

[OCarlos]

Emgrand EC718 automatic transmission jerks during start-up due to lean air-fuel mixture, delayed ignition, weak spark, or transmission malfunction. Symptoms of engine acceleration weakness: When the engine is running, pressing the accelerator pedal doesn't immediately increase RPM, showing sluggish response. During acceleration, engine vibration and RPM fluctuation may occur, sometimes accompanied by backfire or popping sounds. Specific causes of engine acceleration weakness: Intake manifold leaks causing lean air-fuel mixture; low fuel pressure; clogged fuel injectors or fuel filters reducing fuel delivery; malfunctioning sensors (air flow meter, intake manifold absolute pressure sensor, throttle position sensor) failing to increase fuel supply properly; incorrect ignition timing due to faulty sensor signals; weak spark from faulty spark plugs, ignition coils or high-tension wires; dirty throttle body; malfunctioning EGR system; clogged exhaust pipe; low cylinder compression; turbocharger system failure.