i have a 97 ram 1500 club cab 5.9 sport with 240,000 miles. when i got the truck it was running rough so i took it to autozone and they said it was a multiple cylinder misfire. I put new plugs and wires in it and it seemed to run fine. A month and a half later it was running rough again so i took it back to autozone and pulled the codes and adgain it was a multiple cylinder misfire. I changed the cap and rotor and that worked for a week and now it is running rough again, probably another misfire problem. What is going on and can anybody shed some light on this problem and give me some ideas as to what it might be?