I bought a 2002 wrx in june and have been noticing some problems with a backfire. I used this forum and it took me about 2 hours from start to finish to change my spark plugs. I found that the plugs in there were copper not platinum and there was practically no gap on them. I called a few places in town and the cheapest shop was going to charge me $180 if I brought in my own plugs. This was an awesome help and I am hoping to find an easy write up to help me install some coilovers next week.