Will my check engine light code come back on if I clear it?

Will my check engine light come back on if I clear it? Welcome to Mercie J auto care, where compassion and craftsmanship come together. I'm Rick Smith, master certified technician. There’s probably 80 different things that can cause a check engine light to come on and some of those things, the light will come back on very quickly. With some of those things, it may take multiple road test to do so. For example, if you’re if you have an actual rough running engine, you have a misfire, the light is probably going to come back on very quickly and it’s gonna misfire. Sometimes you might have what we called an evaporative system leak. We test the integrity of the entire system from the fuel tank all the way to the engine to make sure we don’t release vapors into the air. That almost always takes multiple drives. It has to have cool down cycles when the car is off, warm up cycles and it’ll only check it between a quarter and 3/4 of a tank. Therefore the light may not come back on for a long time. Maybe it cleared the code, you tighten the cap and maybe the light won't come back on at all. So there’s a lot of variables with check engine lights but if your light goes off on its own and that means it sees everything‘s OK now. If you still want to know what it saw previously, typically the code will stay in the system for about 50 restarts so you should be able to see the code for sometime after the light even goes off. So to answer your question, if I clear the light, maybe I’ll come back on, maybe I won’t. It just depends on what’s going on with your car. Hope this helps you understand the check engine light a little bit more. Thanks for watching until next time safe travels and blessings to you.