I own a 2008 Ford F-150 with 63,000 original miles on it. Automatic transmission. It began to stutter ever so slightly during acceleration. Seemed to need a tune up. A mechanic said it needed new plugs. He called me to tell me that they were breaking off, after he only did two so far. He then linked me to a forum on the Ford spark plugs issue. He said he would charge me only for the ones that broke. The next day, he called and said the other 6 came out without breaking. He linked me to the replacement plugs he supposedly installed. My truck then passed inspection. Since I got it from him, the cab smells like raw gas inside. He said it has nothing to do with the plug replacement. I never had the gas smell before. How can I check to see if he replaced all 8? My son in law worked there before he went into another career and has stated that he scams folks. Any ideas about the gas smell? BTW, the engine stuttering did stop after the work.