How does Chevy AFM work?

How Chevy AFM Works
Chevy’s Active Fuel Management (AFM) is a technology that improves gas mileage by shutting down half of the engine’s cylinders under light-load conditions to reduce fuel consumption. Here’s how it works:
– Functionality: AFM uses a combination of simple hydraulic valves and sophisticated software to switch off the cylinders when the driver doesn’t need full power. When more power is needed, the system seamlessly reengages the additional cylinders.
– Improved Version: In January 2018, GM announced an improved version of AFM called Dynamic Fuel Management (DFM) to be initially released in Chevy Silverado trucks. This system shuts off any number of cylinders in a variety of combinations, maximizing fuel economy and avoiding switching between banks of cylinders.
– Preventing Problems: Disabling or deleting AFM can prevent engine problems, reduce oil consumption, and provide a consistent V8 power experience.
– Disabling AFM: There are two options to fix AFM issues on Vortec engines: disabling the AFM system by adjusting the engine’s ECU so that it never activates AFM, or completely deleting it by replacing all the special parts with standard non-AFM parts.
– AFM Disabler: The Range AFM/DFM Disabler allows your V6 or V8 GM vehicle to run in full cylinder mode at all times, preventing the Active and Dynamic Fuel Management systems from dropping cylinders, ensuring 100% power at all times.
In summary, Chevy’s AFM technology is designed to improve fuel economy by deactivating half of the engine’s cylinders under light-load conditions, with options available to disable or delete the system for those seeking a different driving experience or to prevent potential engine problems.

What is the problem with the Active Fuel Management system?

Common issues include:

• Oil consumption greater than one quart per 1000 miles.
• Combustion chamber deposits resulting in excessive pinging and fuel mileage drop.
• Lifter and/or camshaft failure.
• Engine failure due to ring issues.

How do I know if my AFM is failing?

Look for the following: 1) Lifter rollers that are pitted or gouged with a crater like appearance. 2) Flat spots on a lifter roller due to lifter guide wear/damage, which allows the lifter to turn in the guide promoting misalignment with the camshaft lobe.

Why do AFM lifters fail?

We have found that most lifter faults are caused by oil pressure issues, or control issues. The AFM activation and deactivation is controlled by the Valve Lifter Oil Manifold or VLOM.

Does AFM cause engine damage?

However, the design is not without its flaws. The system designed to shut off half the cylinders using special lifters, also causes irreparable damage to the camshaft and lifter due to very common failures.

Can GM AFM be turned off?

The Range AFM/DFM Disabler allows your V6 or V8 GM vehicle to run in full cylinder mode at all times, preventing the Active and Dynamic Fuel Management systems from dropping cylinders. Our patented technology is the only product that will disable Active or Dynamic Fuel Management without reprogramming the factory ECU.

Does Active Fuel Management really work?

Estimated performance on EPA tests shows a 5.5–7.5% improvement in fuel economy. GM’s Active Fuel Management technology used a solenoid to deactivate the lifters on selected cylinders of a pushrod V-layout engine.

What cylinders shut off with AFM?

AFM (Active Fuel Management)
To provide maximum fuel economy under light load driving conditions, the engine control module (ECM) will command the cylinder deactivation system ON to deactivate engine cylinders 1, 7, 6, and 4, switching to a V4 mode.

Will disabling AFM void warranty?

Because no tuning is involved with your vehicle’s computer, this product will not void the factory warranty. Not only does the AFM Disabler keep your vehicle running smoothly, but it will also have you running on all cylinders, all the time.

Does AFM actually save fuel?

Range AFM Plus works with your factory installed AFM allowing your vehicle to drive in V4 mode up to 80% of the time, maximizing your fuel and dollar savings. The average driver can save approximately 65 gallons of gas per year or about $250.

What are the disadvantages of cylinder deactivation?

If the engine is equipped with a cylinder deactivation system, we face a new potential failure mode. Increasing the valvespring pressure or just increasing the amount of lifter movement at speed may be enough to overwhelm the oil pressure keeping the lifter in full operation.