Depends on a few things. Mine is old non progressive. It comes on at 19 psi. I found that with alcy off it shows 0- or close KR on the scanM at 19 psi on a 65 degree day with this turbo, that's with pump gas and some 104 fuel additive, so it doesn't come on till then. Turbo and IC seems to be efficient from the scanner. So I don't use it very fast, but I only drive the car about 300 miles a year. If you get on it more and with a progressive type that comes on sooner in the boost range, like 12psi, then maybe you'll use it faster. I don't usually get into 20 psi just driving around town.