I have a 2003 Miata, at 69,765 miles I took it in for State Inspection, an oil/filter change and to have the left side fog lamp replaced. Then to the Body shop to have the trunk where the spoiler sits repaired, (found some rust causing water to leak into the battery compartment). I got the vehicle back and the check engine light came on. I took the vehicle back to the repair facility and had new spark plugs installed. code came up as P0300, random misfire. Check engine light was off when I left the facility, but came back on, before I got the vehicle home. We have done a compression test, all is good, cleared the corbon, cleaned out the fuel lines, injectors, new fuel filter, cleaned the gas tank, still comes up with a misfire code and check engine light comes back on. The vehicle has been back to the Dealer several times, this last time the computer was replaced and, Cat code came up so a new Cat was shipped in for replacement. We have changed out one of the ignition coils and the vehicle does not act up like it did, but check engine light came back on. Anyone experienced this problem in the past?