Hey scotty or any other moderator, I have a 2003 toyota corolla, 214k miles, automatic transmission, 2 weeks ago the check engine light came on for code P0302, however after 3 days it went away by itself, then it came back for another 2 days, went by itself came back again and its been 2 days that its been gone again. I went to autozone and used their scan tools to scan in the obd 2 port, I have my mistrust as when they gave me the paper of what code it was, it read a different vin number. Are auto zone scan tools good enough? I recently replaced spark plugs and air filter at 206k miles. Also been averaging about 25 mpg combined city/highway, any recomendations? thanks