BCBMDE, as I said before, I did not switch out my actual sensor, only the housing. [color:"red"] [/color] There is nothing wrong with the MAF sensor. I state again. [color:"black"] [/color] The only thing changed is the housing. If anyone were to actually look at the stock MAF in your Isuzu and take off the screen, you would see what I am talking about how restrictive it is. Even taking into consideration using a non-altered throttle body, the MAF is the biggest constriction in the entire intake. Short of putting an air-flow meter in the intake to measure cfm, it's definately pulling more air. I assumed, and we all know what happens there, that the ECM would be able to adjust automatically. Apparently not. I will be able to tell for sure when I get my gauge hooked up tonight when I get home. And for the record, when I purchased my MAF ends (used), I also got free a MAF that was for that size intake. I tried it as well, and got the exact same results. The only difference that one can even tell is that there is a little extra plastic on 2 small tabs due to the smaller opening that protrudes into the MAF body. Instead of trying to pick holes in an installation, which I am fairly meticulous about, please someone give me some concrete knowledge to go against a lean air/fuel ratio. I think Randii was on the money about the fuel map being offset due to a lower flow rate. Everything I've read about using NOS, Supercharger, and Turbos point to having to adjust EFI's to take into account the extra volume of air.