I have a 2010 5.3 liter silverado truck with the active fuel management system that drops cylinders to save gas. The switch is noticable and runs very rough in the V4 mode. You can feel the truck loose power to the point it switches back to V8 mode. Dealership says its normal; however, I owned a 08 Tahoe with the same system and it worked flawlessly.

I don't believe it is normal and can't get dealer aid. Anyone familiar with issue and resolutions???

 

I have an 08 with the active fuel management. It is very obvious when the system is active. I can tell you that when my truck had an aftermarket exhaust, it was much, much, much worse. Went back to stock, much better but still noticeable. I would love to know if there is a way to turn it on and off when we want to (some kind of 3 way switch you can flip that would keep it in the 4 cyl mode or 8 cyl mode or the stock automatic setting).

 

I agree. I would love to be able to turn it off or on if it is going to be so noticable during normal operation. I would disable until on a long road trip.

If I can't fix it, can I turn it off??

 

Let me add to this. Can I turn it off without screwing up remaining extended warranty?????

 

I think you can have it turned off by a custom tune. I think BB tunes can do it. BUT, the dealer will know if you have a tune done. The ONLY way around this I have found, is to install another PCM with the new tune. and when you do to the dealer for any MAJOR work, reinstall your old PCM with the factory original tune.

Now, a word of caution, if you go to the dealer for say an oil change and they do some kinda free system update to the PCM, and you leave the second pcm in there (because hey, they are only doing an oil change right?), the updates will not be in the factory PCM (since it is in your garage). Now if you have, say a tranny go boom, the dealer has to (warranty division makes them take pictures of this and send it to them) verify that the current tune on the pcm is the same as the one GM has in it's records. So any discrepancies, and the GM warranty division assumes you had a tune and subsequently put the stock tune back in before returning to the dealer (which is a correct assumption) and void your warranty. So, to be safe you would have to reinstall your old pcm every time you brought your truck to the dealer.

can become a pain in the tooshh...