I took my vehicle into the dealership to have the timing set, radiator replaced, and new spark plugs put in. When I picked up my vehicle it still ran terrible and had a miss. The service manager told me to replace the plug wires and it would run great. So I did. My van still ran horrible. After a day my motor started knocking terribly and began backfiring. I checked the spark plugs and they were all damaged. Some were broke, literally came apart inside, and others were cracked. I took all 6 plugs to the dealership and spoke with the service manager. He excused himself and did not return. when I asked where he had gone no one knew. When I asked to speak to the owner the employee could not even tell me the owners name. I left very upset. My motor is now ruined due to the plugs coming apart and the pieces going into my block, and damaging my pistons. I feel they should replace my motor but can't get anyone to help me.