When a programmer or chip is used on a Power Stroke, it will increase the boost pressure causing the computer to de-fuel in an effort to bring boost pressure back down. Sometimes it causes a check engine light, but on some trucks it will de-fuel without a code. In several cases, we have seen a power increase on the dyno simply by adding the Over Boost Kit. The computer will usually trip the over boost condition and give a code at 24psi and de-fuel the truck. This regulator goes in between the MAP sensor and intake to allow the MAP sensor to see only 22psi. The regulator is adjustable and easily installed.