Active Fuel Management – Gas Saver or Engine Killer

Active Fuel Management or originally named Displacement on Demand (DoD) motors allow a V8 access to the mile per gallon fuel economy of a smaller 4 cylinder motor with the on demand ability to access more power when needed, instantly. 

Active Fuel Management

The thought process behind the new design was to allow the consumer to have the ability to enjoy both a fuel efficient motor while also having the power and performance of a bigger V8 engine. To do this the AFM (Active Fuel Management) shuts down half of the engine’s cylinders during driving, for example during highway driving. 

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. A quick google search , AFM Failure , leads you to countless blogs and videos about the lifter seizing or coming apart and causing damage to the camshaft (internal motor parts that are extremely expensive to replace). If a lifter comes apart, the pieces of metal from the camshaft or lifter itself can be spread through the entire system and therefore causing issues to the entire oiling system. Because these metal shavings can be microscopic it is difficult to get them all out and the risk of further failure is still present so long as there is unaccounted for metal in the engine components.

The diagnostic on this issue can be tricky in itself, presenting most commonly as a misfire code (P0300; ect) The common tech savvy person would assume a plug or coil issue and replace that and continue to drive. However if it is the lifter the continued driving can cause thousands of dollars in damages and void warranties. We take the time to test the misfire to ensure the issue is not the lifter failure. 

Lifter Comparison

But you don’t have to wait until the failure occurs to avoid costly bills. We can deactivate the AFM on your vehicle for $349 ; this will allow all the lifters to work all the time and stay lubricated effectively. The fuel mileage is rarely affected allowing you to continue the same MPG you had before we deactivated the AFM to save thousands of dollars on repairs! Not to mention the hassle of being broke down on the side of the road or in a strange city on vacation. 

Call us now to turn off your AFM OR to properly diagnose your misfire codes at 850-862-6868.

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