No, the check engine light will still come on, if something craters. Oh, and it'll come on again (and need you to flip the switch BACK) at 120,000 I know, and maybe at 100,000 (not sure, it's been a LONG time since I saw 100,000 on any of my Kicks). So every time it comes on, just move it to the "other" position. If it's a mileage thing, it'll turn off - if it's a real malfunction, it'won't turn off, but be SURE to move the switch back, or you won't know when you've fixed the problem.