8-4 deactivation
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
Likes: 3,954
From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Engine speed is between 700 and 2800rpm
Engine oil pressure is between 187–455kPa (27–66psi)
Engine coolant temperature is between 40–129°C (100–264°F)
Engine oil temperature is between 16–128°C (61–263°F)
Throttle angle is 6% or less
Transmission is not in first, second, or reverse gear
Vehicle speed is greater than 25kph (15.5mph)
Vehicle is not in fuel shut off mode
Vehicle is not in heater performance mode
Vehicle is not in tip in bump acceleration mode
Vehicle is not in oil aeration mode
To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
2, 4, 6, 8, Passenger side from front to rear.
1, 3, 5, 7, Driver's side from front to rear
Active Fuel Management (AFM), which shuts down the LT1’s firing cylinders from eight to four by disabling the valves to the cylinders. When AFM initiates, the engine turns the 6.2L V8 into a 3.1L V4, shutting down cylinders 1, 4, 6 and 7, and firing only cylinders 8, 2, 5 and 3 in that order.
Otherwise, the complete firing order is 1, 8, 7, 2, 6, 5, 4, 3.
Elmer
Engine oil pressure is between 187–455kPa (27–66psi)
Engine coolant temperature is between 40–129°C (100–264°F)
Engine oil temperature is between 16–128°C (61–263°F)
Throttle angle is 6% or less
Transmission is not in first, second, or reverse gear
Vehicle speed is greater than 25kph (15.5mph)
Vehicle is not in fuel shut off mode
Vehicle is not in heater performance mode
Vehicle is not in tip in bump acceleration mode
Vehicle is not in oil aeration mode
To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
2, 4, 6, 8, Passenger side from front to rear.
1, 3, 5, 7, Driver's side from front to rear
Active Fuel Management (AFM), which shuts down the LT1’s firing cylinders from eight to four by disabling the valves to the cylinders. When AFM initiates, the engine turns the 6.2L V8 into a 3.1L V4, shutting down cylinders 1, 4, 6 and 7, and firing only cylinders 8, 2, 5 and 3 in that order.
Otherwise, the complete firing order is 1, 8, 7, 2, 6, 5, 4, 3.
Elmer
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
Likes: 3,954
From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Racer
Joined: Feb 2020
Posts: 305
Likes: 245
From: GSO, NC
Engine speed is between 700 and 2800rpm
Engine oil pressure is between 187–455kPa (27–66psi)
Engine coolant temperature is between 40–129°C (100–264°F)
Engine oil temperature is between 16–128°C (61–263°F)
Throttle angle is 6% or less
Transmission is not in first, second, or reverse gear
Vehicle speed is greater than 25kph (15.5mph)
Vehicle is not in fuel shut off mode
Vehicle is not in heater performance mode
Vehicle is not in tip in bump acceleration mode
Vehicle is not in oil aeration mode
To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
2, 4, 6, 8, Passenger side from front to rear.
1, 3, 5, 7, Driver's side from front to rear
Active Fuel Management (AFM), which shuts down the LT1’s firing cylinders from eight to four by disabling the valves to the cylinders. When AFM initiates, the engine turns the 6.2L V8 into a 3.1L V4, shutting down cylinders 1, 4, 6 and 7, and firing only cylinders 8, 2, 5 and 3 in that order.
Otherwise, the complete firing order is 1, 8, 7, 2, 6, 5, 4, 3.
Elmer
Engine oil pressure is between 187–455kPa (27–66psi)
Engine coolant temperature is between 40–129°C (100–264°F)
Engine oil temperature is between 16–128°C (61–263°F)
Throttle angle is 6% or less
Transmission is not in first, second, or reverse gear
Vehicle speed is greater than 25kph (15.5mph)
Vehicle is not in fuel shut off mode
Vehicle is not in heater performance mode
Vehicle is not in tip in bump acceleration mode
Vehicle is not in oil aeration mode
To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
2, 4, 6, 8, Passenger side from front to rear.
1, 3, 5, 7, Driver's side from front to rear
Active Fuel Management (AFM), which shuts down the LT1’s firing cylinders from eight to four by disabling the valves to the cylinders. When AFM initiates, the engine turns the 6.2L V8 into a 3.1L V4, shutting down cylinders 1, 4, 6 and 7, and firing only cylinders 8, 2, 5 and 3 in that order.
Otherwise, the complete firing order is 1, 8, 7, 2, 6, 5, 4, 3.
Elmer
Thank you so much for all the answers you have provided (and keep providing) thru the years.
Best regards,
Vip.
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
Likes: 3,954
From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Elmer
