GM > Engine > Torque Management > General

Maximum Torque
The values affect the maximum torque allowed by the VCM. Many of these values only apply to Electronic throttle control vehicles.

• Max Engine Torque vs. RPM vs. Gear: Maximum allowed engine torque vs. RPM and current gear for transmission protection. Electronic Throttle Fitted Vehicles only.
• Max Torque vs. Gear: Maximum allowed engine torque vs. current gear.
• Max Torque vs. RPM: Maximum allowed engine torque vs. RPM, whilst TCC locked.
• Max Torque: Maximum allowed engine torque for Electronic Throttle Control fitted vehicles. This value is also used to control a torque based PCM output, this is used on some Holden vehicles to reduce Fuel Pump voltage when torque is below this value. WARNING: increasing this value on those vehicles will result in reduced fuel pressure, lean conditions and possible engine damage during high torque operation.

  
  

• Max Torque - 4WD Low: Maximum allowed engine torque vs. current gear when in 4WD Low range.
• Max Torque - 4WD High: Maximum allowed engine torque vs. current gear when in 4WD High range.

  
  

• Tip In Torque by Gear: Electronic throttle maximum allowed instantaneous torque increase based on automatic trans current gear.

  
  

• Trans Input Torque Max: Maximum Transmission Input Torque
• Trans Output Torque Max: Maximum Transmission Output Torque
• Front Axle Torque Max: Maximum Front Axle Torque (4WD applications)
• Front Propshaft Torque Max: Maximum Front Propshaft Torque (4WD applications)
• Rear Axle Torque Max: Maximum Rear Axle Torque
• Rear Propshaft Torque max: Maximum Rear Propshaft Torque

  
  

• Brake Torque Limit: Maximum torque during braking, to ensure the vehicle brakes can always stop the vehicle.
• Brake Torque Limit vs. Pedal: Maximum allowed torque with brakes applied.
• EGT Torque Limit vs. RPM: Maximum allowed torque when exhaust gas overtemperature is detected.

ETC Limits

• ETC TPS% Max: This is the maximum allowed ETC throttle percent based on the current percentage of torque being delivered. The PCM uses this to limit the ETC opening rate to maintain traction.
• ETC Injector Disable: During ETC Traction control strategies the PCM may disable injectors in order to control engine torque. This table is an 8bit binary "Enable Mask". A value of "0" for any bit means that cylinder will be disabled. A value of 255 means all cylinders will remain enabled.
• Power-Hop Injector Disable: Disables injectors during a very large torque transient. This table is an 8bit binary "Enable Mask". A value of "0" for any bit means that cylinder will be disabled. A value of 255 means all cylinders will remain enabled.

  
  

• ETC TPS Max vs. Mode: This is the maximum allowed ETC throttle position in relation to traction control mode and gear.
• ETC TPS Max vs. Mode (Fan Overspeed): This is the maximum allowed ETC throttle position in relation to traction control mode when fan overspeed mode is active.
• ETC TPS Max vs. ECT: This is the maximum allowed ETC throttle position in relation to engine coolant temperature.
• ETC TPS Max vs. Oil Temp: This is the maximum allowed ETC throttle position in relation to engine oil temperature.
• ETC TPS Max Delta Positive: This is the maximum allowed ETC throttle position rate of change during throttle opening versus RPM and gear.

Spark Retard

• Max Torque vs. RPM vs. Gear: The values affect the amount of spark retard commanded by the VCM to achieve the desired % Torque Reduction. Setting this table to zero will disable any torque management related spark retard, including transmission shift torque reduction.
• % Torque Loss vs. Spark Retard: This table is the inverse of the other table and tells the PCM how much torque is lost for a given amount of spark retard.

Traction Control System (TCS)
The values affect the amount of retard the VCM will use to reduce engine power due to loss of traction.

• Traction Control Spark Retard vs. RPM: Normal TCS retard (degrees)
• Traction Control Air Fuel Ratio:
• Traction Control Aggressive Spark Retard vs. RPM: Aggressive TCS retard (degrees)
• Traction Control Injector Disable: Specifies the number of injectors disabled by the TCS system for each mode (V6 only)
• Traction Control Max Torque: Specifies the torque reference for retarding ignition timing during TCS operation. The lower this is set, the earlier the VCM will retard timing during TCS. (V6 only)

  
  

• TCS Limit - Spark: Traction control will use spark if enabled.
• TCS Limit - Fuel Cut: Traction control will use fuel cut if enabled.
• TCS Limit - ETC: Traction control will use ETC if enabled.

  
  

• TCS Enable Temp: Traction control will be enabled if ECT is above this.
• Minimum Desired Torque: Traction control torque request will be limited to greater than this.

  
  

• Powerhop Enable: Powerhop (axle tramp) control enable/disable.
• Powerhop Limit - Spark: Powerhop (axle tramp) control will use spark if enabled.
• Powerhop Limit - Fuel Cut: Powerhop (axle tramp) control will use fuel cut if enabled.