About 2,000 miles ago I replaced my spark plugs with Bosch Fusion plugs. You know, the ones with 4 tips on them. Cost me $10 each. About 300-400 miles ago I got a after driving 50 miles or so after getting some gas (not a full tank). I drove about 150 miles with it before I could get the code read at Autozone. But before I got to Autozone I filled up with gas again, this time all the way full. When I turned the car back on the CEL went away. I went to Autozone anyways and they were able to pull the code. The code read: Multiple Random Misfires. I'd been noticing something that felt like that while cruising. A slight hesitation almost not noticeable. The code still hasn't come back in but I wanted to go to the dealership to see what they would say. When I was describing the problem the service rep said that it was because I was using Bosch plugs and that the only plugs that ANY Japanese built car could use were NGK plugs, also at $10 each (never heard of them before). Does this sound right or is the dealership trying to make a quick buck? I don't think my plugs are the problem I've always used Bosch products (including plugs) and NEVER had any problem with them at all. I pulled the plugs and they all looked just fine. All the wires are on tight and I don't hear any misfires. The car starts like new every time. I did have a problem at about 4500 miles with my fuel pump but the dealership said it was a known issue on some 3's and they fixed it under warranty. Could that be the problem? How bout a dirty fuel injector? I'm not sure what else to check. I just don't want to go into the dealership and they tell me it was the plugs and that not be the real problem. Suggestions?