I went back to have my van checked out because the engine was running rough after I told them that it was the spark plug because I just recently replaced it. I also told them that it wasn't like that before I replaced the old one. But sure enough I was charge the diagnostic fee and all together it cost me close to $200. $200 to replace one spark plug . In addition to that no one called me to authorize the work that is going to be over $100. I will not go back to have my cars worked on because ikc Martin is a rip off.