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How to Diagnose Active Fuel Management Problems

If you drive a vehicle equipped with a 5.3L V8 with variable displacement technology, you may be suffering from Active Fuel Management. This system helps to cut fuel and oil use by turning on and off depending on the conditions. It normally kicks in when the car is light-loaded, which can increase fuel economy by as much as 7.5%. If you’re wondering how to diagnose Active Fuel Management problems, read on. The following are just some of the common problems associated with Active Fuel Management.

Lifter failure

The lifter in an engine is the component that controls active fuel management, also known as AFM. If the lifter fails, it can cause a variety of problems. These problems can cause additional damage to other parts of the car, such as the clutch, flywheel, or transmission. Failure of the lifter can be a major cause of vehicle stalling and misfiring. You should immediately replace a failing lifter to prevent further damage.

Bad lifters may cause a number of symptoms, including a check engine light, rough running, or complete shutdown. Other symptoms of lifter failure include a reoccurring ticking or knocking noise, or a bent pushrod. If you suspect your car is having one of these issues, see your mechanic as soon as possible. While parts availability has been an issue, most vehicles can be repaired if diagnosed and fixed quickly.

The most common AFM problem is a failed lifter. The lifter can fail due to a number of reasons, including lack of oil, low oil levels, and poor lubrication. When a lifter fails, it can result in a number of other issues, including indents in the oil seals. If a lifter fails, you should replace the lifter guides and oil filter.

The problems with GM lifters affect certain models of the Chevrolet Silverado and GMC Sierra pickups. However, the problems also affect the GMC Yukon, GMC Suburban, and Cadillac Escalade. Fortunately, the fix for the GM lifter problem appears to be working. As a result, you should avoid buying any of these vehicles. Lifter failures can be a major cause of vehicle failure, so it’s best to take action before the problems become too severe.

General Motors has a class action lawsuit pending against it for selling vehicles with defective fuel management lifters. The lawsuit claims that GM replaced the defective parts with equally faulty ones. Symptoms of this problem include stalling, sudden loss of power, and hesitation when merging. These symptoms can be extremely dangerous, especially for drivers who are already in motion. These problems require expensive repairs to fix. If you have an affected vehicle, you should contact your local dealership immediately.

Oil consumption

Chevy and GMC vehicles are affected by problems with Active Fuel Management. These cars use a computer system that can cause excessive oil consumption and damage to engine components. Although the fix for this problem has been out since April 2013, it doesn’t always work. The problem is not as widespread as many consumers believe. Here are some troubleshooting tips and tricks to fix this problem. Read on to learn how to fix the problem yourself!

Deactivating Active Fuel Management (AFM) may seem like an effective way to fix the problem. But it’s not a permanent solution. Deactivating it will only result in worsened oil consumption and will reduce MPG by as much as 20%. The problem can also lead to shuddering when switching from running on half of cylinders to running on all of them. Deactivating the system is only effective if you can drive without it.

There are many ways to fix GM 5.3L oil consumption problems. GM dealerships typically replace the valve covers, oil deflector, and pistons and rings. However, an aftermarket device can disable the Active Fuel Management system and fix the oil leak problem. This device also allows you to change the programming of the engine module. However, you should consider that it will only help your engine run smoothly if you’re not using it.

AFM can be an expensive solution for excessive oil consumption. While it’s not always possible to stop AFM from disabling the entire engine, removing it from the vehicle’s computer can help solve the problem. AFM has been the cause of many problems with Vortec engines. This engine features a special oil pressure relief valve and high-volume oil pump to control oil pressure. If you disable the AFM, you won’t need to replace the engine’s lifter.

In 2005, General Motors engineers developed Active Fuel Management. In this system, the engine shuts off half of its cylinders when it’s not in use, reducing oil consumption. A more advanced version of this technology is called Dynamic Fuel Management and has seventeen patterns depending on inputs such as temperature and engine load. While these changes may make the car more fuel-efficient, they can also cause internal engine damage.


One of the most common causes of engine misfire is an improperly functioning fuel system. When your car’s active fuel management system fails, one or more cylinders don’t produce enough power to complete the combustion. The culprit may be the spark or fuel, clogged injector, or faulty oxygen sensor. You may experience slower acceleration, shaking or jerking at idle, or a check engine light. Misfires also reduce fuel efficiency, as unburned gasoline can exit the engine without being burned.

A misfire can also be caused by improper air flow or fuel balance. If your fuel injector is not working properly, air may enter the combustion chamber, resulting in an engine misfire. A faulty spark plug could be the cause of the misfire. The ignition coil packs can fail, and the wiring may wear out. Without proper electricity, the spark plug will not be able to ignite. If the problem persists, you may have to replace your fuel injector.

AFM is a technology developed by General Motors to save fuel in light-road conditions. The technology allows V6 and V8 engines to shut down half of their cylinders and increase fuel efficiency. Unfortunately, the result is engine misfires. The fuel management system was originally designed to increase horsepower, but now the fuel efficiency is at risk. As a result, your mileage will be lower than before. If this sounds familiar, you’re not alone.

If the misfire persists, it may be an issue with the fuel system or with a malfunctioning sensor. An obstructive sensor could be the culprit. An incorrectly functioning fuel pressure regulator can also cause misfires. Also, a faulty fuel pressure regulator may cause a vehicle to run leanly or richly. If you suspect that a malfunction is causing your misfire, plug in a code reader and check the malfunctioning engine-control unit. You can also check the spark burn line to see if there’s any activity. A little hash is normal, but if it is very thick, then you have an ignition problem.

In some cases, the error may be caused by a malfunction in a specific cylinder. Usually, cylinder five is the culprit. The ECM detects a misfire and sends the Check Engine light on. If the misfire is the culprit, the ECM needs to relearn the process. This process may cost as much as $1700 or more. However, it is not necessary to replace the engine or change the fuel system if it has a simple malfunction.

Cost of repair

Fortunately, the cost of repairing an active fuel management problem is usually covered by the power-train warranty of a Chevy truck. If you’ve had an active fuel management problem in your Chevy truck, read this article to learn more about the most common symptoms and costs of repair. The system is designed to increase fuel efficiency by disabling half of the cylinders when engine load is low. This is more effective in light-road conditions, which is what causes the vast majority of complaints.

A common problem caused by AFM is excessive oil consumption. It’s caused by faulty oil monitoring systems and can also result in lifter failure, which isn’t a cheap repair. In order to prevent this problem, you can disable your active fuel management system, which is built into various Vortec engines. To disable the AFM, you should know the specific engine code. This code is located on the engine’s fuel injection module.

The easiest way to disable active fuel management is to use a device that tricked your vehicle’s ECU into thinking it’s in V8 mode. This device plugs into your vehicle’s OBDII port and will start working immediately. You can then remove the device when you no longer need it. But be aware that disabling AFM is not a permanent solution. If the problem has already occurred, you should visit a mechanic for the repair.

Replacing the lifters is an expensive and labor-intensive repair. It can cost you anywhere from $1000 to $2,500 to repair an active fuel management problem. It may also cause excessive oil consumption and ring and cylinder wear. Depending on the damage, it may lead to the need for engine replacement. So, if you want to have your Chevy’s active fuel management problems fixed, you should read this article.