Will bad gas cause your check engine light to come on?
According to my smog check guy, John, YES.I hadn’t been driving one of my cars much when I took it in for a smog check required in California for renewal of registration. I told him the car tends to stall and might need to have the throttle body cleaned. He said that probably wouldn’t be a problem, but put the gizmo on it that reads out error codes.Hmm he says, looks like you haven’t been driving it enough. You need to drive about 50 or 60 miles to clear out a couple of error codes, then come back.So I put in about half a tank of gas and drove for an hour or so and came back. At that point the check engine light had come on. John checks the error codes again.Oh! You’ve got a 420 code! That’s some kind of problem with the catalytic converter system. What kind of gas are you using?Arco, regular, the cheapest one.Oh! Well you’ve got to drain that and put in some better gas, Chevron or Shell, 91 octane. Then drive a hundred miles or so. That should clear it up.So I’m in the process of driving off the remaining half tank of Arco, after which I’ll fill her up with the good stuff and drive another hundred miles or so before going back to see if my car can pass the smog test…