I don't know what the hell to do. I've got some pretty good mods that have made my car haul a$*. The problem is, I've still got a slight ping/rattle at WOT. It runs perfect at everyday speeds, and even at 5000 rpm with 1/2 throttle it does not ping. I've got 27000K, I don't think that the fuel filter has been changed. Someone told me to upgrade my 01 19lb injectors to 21lbs, but I don't really think I have to considering I've only added 30+ hp. I've put the fuel injector cleaner in, and made sure all fluids and filters are clean. Another point, it made it the same sound around 14k when all I had was a K&N and welded in flows. I make enough money to pay for a dyno tune, but I just hate to spend 400 bucks every month on a mod. What do I do fellas?