Engine Speed Limitation

To protect engine, torque converter and powertrain, the engine control module limits engine speed under specific operating conditions. Engine speed is limited by leaning out air/fuel mixture or fuel injection is stopped and ignition is retarded.

Torque converter is protected when transmission is in Park or Neutral because torque converter is subject to increased internal static pressure. When transmission is in Park or in Neutral with vehicle speeds more than 3 MPH, engine speed is limited to 4000 RPM.

Powertrain is protected to reduce extreme acceleration (takeoff) effects. During takeoff, engine speed is limited to 3500 RPM for one second when engaging transmission in gear when vehicle speed is less than 18 MPH.

To protect engine from damage, engine speed is limited for 3.5 seconds when engine speed is 6550-6650 RPM, then engine speed is limited continuously (no time limit) at 6350-6450 RPM.