AFM - I don't notice anything

[Tjaas]

How can I tell when it kicks in???

I bought my car used from the dealer, not sure it had a tune or not. It does shift hard from 1st - 2nd

2010 SS/RS
L99

[daveagogo1]

Cruise along at about 1200 rpms at a steady speed. You should hear it kick in. Kind of a wierd note in the exhaust and a slight rumble / vibration. It may have been tuned out.

[Mr_Draco]

If it's a stock exhaust, you won't hear it kick in nor feel any difference.

[Rcfiddy1]

You will feel it while cruising as you try to accelerate it will feel as there is a delay in throttle as the car kicks off afm. You should aslo hear it with the stock exhaust.

[daveagogo1]

Originally Posted by Mr_Draco

If it's a stock exhaust, you won't hear it kick in nor feel any difference.

Sorry but yes you do. Both sound and feel. Minor on stock but it is there and unmistakable.

[orangejuice]

Its definitely there with the stock exhaust.

[Mr_Draco]

Well I for one never noticed it when I was stock. It wasn't until I changed out my axle back that I could tell it was kicking in. When I got my headers installed it was tuned out so it wasn't an issue.

[Tjaas]

I do have aftermarket exhaust ( stainles steel kooks mufflers in place of the stock and no muffler in center, I assume it is a cat back system ). I think it must have been tuned out because I don't notice anything in the 1200 mi I have put on it.

Thanks for the replys

[amz]

Feels bad , sounds bad , and I hear its not so good for the engine.

I got that ridiculous nonsense tuned out of my SS and my daughters Impala SS.

[E.T.]

If you really wanted to know for sure, you could have the dealer hook up their scanner to your car and see if it's tuned.

When cruising along at steady RPMs, the car goes into AFM mode, then when you give it gas it goes back to V8 mode. I could always tell when it was going back to running on all cylinders. As soon as I'd blip the throttle, I'd hear a fart-type sound and maybe just a slight hesitation.

Once you know what to listen and feel for, AFM is unmistakeable.

[GEEKFREEKSCOTTY]

I never noticed it with my stock exhaust because it was too quiet. Once I got aftermarket mufflers, it was only then did I notice it.

If I had returned to stock mufflers now, I could probably tell when it kicks in, because I now know what too look/listen for.

Not that it matters in my case, because after I get my car tuned next week, the AFM will be a thing of the past.

[cam62]

Originally Posted by E.T.

When cruising along at steady RPMs, the car goes into AFM mode, then when you give it gas it goes back to V8 mode. I could always tell when it was going back to running on all cylinders. As soon as I'd blip the throttle, I'd hear a fart-type sound and maybe just a slight hesitation.

Once you know what to listen and feel for, AFM is unmistakeable.

Exactly.. very noticeable to me. Just waiting to tune it out.

[Chevrolet Customer Svc]

Originally Posted by Tjaas

How can I tell when it kicks in???

I bought my car used from the dealer, not sure it had a tune or not. It does shift hard from 1st - 2nd

2010 SS/RS
L99

In your owner's manual on page 8-25 it states:

Vehicles with V8 engines and an automatic transmission have Active Fuel Management™. This system allows the engine to operate on either all or half of its cylinders, depending on the driving conditions.

When less power is required, such as cruising at a constant vehicle speed, the system will operate in the half cylinder mode, allowing the vehicle to achieve better fuel economy. When greater power demands are required, such as accelerating from a stop, passing, or merging onto a freeway, the system will maintain full-cylinder operation.

I hope this information was helpful!

Brandon
Chevrolet Customer Service

[cmore]

Originally Posted by Mr_Draco

If it's a stock exhaust, you won't hear it kick in nor feel any difference.

Mine is stock and have no trouble feeling it just before it returns to 8 cyl. Normally don't notice it drops to 4 cyl.