Tony has worked on my car twice. The first time was to actually re-diagnose a questionable suggestion by another mechanic working for a stealership while the car was under "warranty". He was very thorough with his assessment and quite accurately determined what the problem was. In order to ensure my long term happiness, he went behind the last guys spark plug change to check for proper gap and sure enough all six plugs were widely varied and the wrong type of plug as well. After proper oem replacement was found and properly gapped away we go to "Purring like a Caddy!"