As I understand it, this engine will use only 4 cylinders when the computer sees fit in order to save gas milage. On a Buick, the average highway MPG is estimated to be about 24.

If you drove one of these engines, and you really wanted to watch your gas milage for whatever reason, would it be possible to coerce the computer to use only 4 cylinders as much as possible? For example, if you drove like grandma, would the engine use just 4 cylinders most of the time? If so, what do you estimate the fuel economy would be?

I have the 5.3 in my Pontiac Grand Prix GXP, now mind you I have a heavy foot, I get about 13 around town, on the highway I get about 22.

As I understand it, you want to reprogram the computer to stay in 4-cylinder mode longer. It's not a bad idea, but you'll give up some power. It could be an interesting feature for GM to add to 5.3 equipped vehicles to have "Economy" and "Performance" modes.

As I understand it, you want to reprogram the computer to stay in 4-cylinder mode longer. It's not a bad idea, but you'll give up some power. It could be an interesting feature for GM to add to 5.3 equipped vehicles to have "Economy" and "Performance" modes.

I have't thought of it that way, but that's a good idea. It would allow you to have your cake and eat it too.