AFM Lifter Failure Symptoms You Need to Know About

Although AFM lifters are supposed to increase fuel mileage, they seem to have quite a few adverse effects and one of the largest issues has to be an AFM lifter failure. An AFM lifter failure should be fixed immediately or else you will be putting your safety at risk.

However, for you to fix the failure you first have to be able to recognize the AFM lifter failure symptoms. Therefore, today we are going to give you information about AFM lifter faults symptoms, so you can recognize them easily. Additionally, we’ll also be discussing what causes this issue.

afm lifter failure symptoms

Symptoms of AFM Lifter Failure

AFM system is maintained by the valve lifter oil manifold. And there are quite a few AFM lifter failure symptoms, and you need to be aware of all of them to be safe. In the case that the AFM lifter faults go unnoticed your car may get severely damaged, and your health may be also put at risk. The vehicle may also need a reroute of the stock tanks. So, learn about the symptoms below so that you can tackle the issue early.

1. Noticing Low Engine Power

If you have a fully functioning engine that can run at optimum power but you are noticing that it’s giving much lower power, then you should check if there’s an AFM lifter failure. The low engine power could be the result of many issues that are associated with things such as cylinder misfiring. However, you should still check whether it is because of an AFM lifter failure, just to be safe. Alongside the engine power loss, it might display check engine light on the truck dashboard in addition to the engine misfire codes.

2. Downshifting becomes Difficult when Driving

One of the most common symptoms of this failure is that you will notice that you’re having difficulty in downshifting while you are driving. If you find this symptom in your car then there’s a high possibility the AFM lifters have failed.

You have to immediately get on to fixing the damaged active fuel management lifters or else crucial parts of your vehicle such as the clutch may get damaged, which would be a very expensive repair. 

3. Side to Side Jerking While Accelerating

Among the many symptoms of AFM lifter issues, this side-to-side jerking of your vehicle when accelerating is quite a prominent one. If you see that your vehicle begins jerking as you start accelerating, you should immediately park your vehicle in a safe spot. 

This vehicle jerking motion is huge possible danger to you, and may even result in road accidents. Hence, park your vehicle once you notice this issue and get to fixing the failure with the help of an automobile mechanic. 

4. Your Vehicle May Stall all of a Sudden

If your vehicle’s engine stalls all of a sudden without any warning then you might have a case of active fuel management lifter failure in your hands. The sudden stalling is very hazardous, especially if you’re on the highway where cars are traveling at high speeds. It is crucial for you to get your vehicle serviced out at once if your car stalls suddenly.

When driving your vehicle if the V8 engine suddenly stalls then you might lose control which could be very scary, so be sure to get your car serviced from now and then.

5. Vehicle Hesitates to Accelerate

There could be many reasons as to why your vehicle may hesitate when you are accelerating it, and an AFM lifter failure could be one of the reasons. Although this problem is commonly seen as a result of issues including overheating or mass airflow sensor failure, it doesn’t hurt to rule out the possibility of an AFM lifter failure. Moreover, poor acceleration can often cause engine grinding and that can be very damaging for your vehicle.

Also, an active management lifter fault can also lead to lifter tick. If you leave lifter tick unchecked, it may negatively impact your engine power.

How to Stop AFM Lifter Failure

An AFM lifter failure can be a lot of trouble, and the repairing will cost you some good money. Hence, it’s best if you know what you need to do in order to prevent AFM lifter failure.

Disable the AFM

The DOD or AFM system is usually the root behind the AFM lifter failure issue, so the best thing you could do is disable it with an AFM disabler.

Simply plug in the AFM disabler into the OBD2 port to activate it, and deactivate the AFM system. This will cut down the risk of an AFM lifter failure by a lot!

Here are some effective to avoid AFM lifter issues.

Do not Use Low Quality for Your Vehicle

A leading reason of AFM and exhaust valve lifters failure is poor quality oil and oil pressure issues. After using low-quality oil for prolonged periods the AFM lifter might start to break down, and thus cause AFM lifter failures. We are not saying that you have to buy very expensive oil, but buy oil that is of decent quality. This oil change will pay off in the long run and also help with reducing oil consumption.

Get Your Vehicle Serviced Every Now and Then

It is always best to stay cautious with your vehicle and get it serviced regularly to tackle wear and tear. In this way, you can catch issues of your vehicle early on, and won’t have to break the bank to get the repairs done. Moreover, servicing your car by a mechanic will help in eliminating issues that could develop in the future. 


The thought of having an AFM lifter replacement could be daunting considering the risks and the expenses. However, after reading this article on AFM lifter failure symptoms you should be able to notice any of these symptoms immediately. Additionally, now you know what to do to prevent an AFM lifter failure, so you should be safe!

Also, there have been investigations regarding whether some GM vehicles were made with defective AFM lifters, and lawyers were discussing whether they can file a class action lawsuit. So, get some info on this and check if your vehicle model falls within the range of vehicles being investigated.

Related Posts:

Top Range AFM Disabler Forums in 2022

Range AFM Disabler Problems and Solutions in 2022

We Tried Best AFM Disablers in 2022 | Here’re the Winners

How Do I Know If I Have Active Fuel Management? Find Out Now!

How to Disable Active Fuel Management