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8-4 deactivation

Old May 17, 2022 | 01:40 PM
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Default 8-4 deactivation

When the engine goes to 4 cylinders, does it alternate the 4 cylinders or always the same 4?
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Old May 17, 2022 | 02:16 PM
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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
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Old May 17, 2022 | 02:28 PM
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So the answer to my question is NO.
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Old May 17, 2022 | 02:33 PM
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Originally Posted by johnfin
So the answer to my question is NO.

just covering anything else that might pop up in the conversation but, yes, it's no.

ELmer

Last edited by eboggs_jkvl; May 17, 2022 at 02:50 PM.
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Old May 18, 2022 | 02:24 PM
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From: GSO, NC
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Originally Posted by eboggs_jkvl
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
Dang Elmer, Is there anything that you don't know about the C7?
Thank you so much for all the answers you have provided (and keep providing) thru the years.

Best regards,
Vip.
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Old May 18, 2022 | 04:16 PM
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Originally Posted by Vipula AD
Dang Elmer, Is there anything that you don't know about the C7?
Thank you so much for all the answers you have provided (and keep providing) thru the years.

Best regards,
Vip.
I have a very good note keeping system. All that is NOT off the top of my head. I'm extremely talented in copy and paste!

Elmer
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