I Installed My AEM air/fuel Gauge today. The Computer keeps the ratio really close to 14.7 While cruising. when I get on it hard it'll be a constant 12.4. My question is that after running it hard and coming down from like 90 or 100mph with NO throttle, it reads "Off the gauge LEAN" is this OK. I Have the Diablosport tune in it now, Haven't checked with the stock tune. But what do you think? is that Normal to be that lean coming down?

 

I believe that's called DFCO - Deceleration fuel cut-off. After you coast for awhile (a few seconds at 0% TPS) the computer will cut fuel, essentially making your engine just an air pump. I'm not sure if this is for economy or to help decelerate, but that's what it is. It's normal.

 

yep...full lean seems high but it should definitely go over...DFCO. If you have hpt or efi live go in and turn dfco off and see how fuel mileage you lose. It will blow you away.