possible pinging

Hey guys i have a 2004 GT mustang with all the mods in my cig i think i may be getting some part throttle pinging im not really sure if its pinging though it sounds more like my exhaust leak use to before i had it all welded. It only occurs when i have load on teh car not at idle. When i had the diablo tune on it with 93 octane it seemed like it was loosing power trying to get up hills i would have to give it a lot more gas just to maintain 60mph going up a hill. Once i pulled the performance tune back off and returned to stock the noise is still there but it feels like it has more power also gettin up hills.

I really dont think the pinging could be due to having too many flow mods because i even took off my intake system and it still does it so right now all i have is the catback and x. oh and the car has almost 16000 miles on it. I also tried some seafoam in the gas and using it in the intake system but that didnt seem to help but it was fun making some smoke

Any advice you guys could give me??:SNSign:

well its kinda a fast rattling/ticking sound i dont really hear it unless the windows are up and i hit the gas pretty good in basically any gear except 1st. when the windows are down i can only hear it when i go by curbs and guard rails. when i had that maf intake system on i richened my mix before i went to a dyno session(thought i could have been pinging then too) and it only dropped to around 13.0 at 5k. I have had the intake off for about 2 months now. But see the weird thing is when i had my system welded up i didnt have any noise what so ever and then about a week later it sounded like the leak was back so i am thinkin my bolts that connect the x to the manifold might have come loose.

its got some pretty good power still. i was at the track last night with it and ran a 9.2 at 78.5 my only run the car seemed to do real well i bogged bad off the line lol i wasnt ready at all 2.3 60'. it was pulling really hard and i didnt hear any pinging or this rattle when i was there probably cause the engine is so loud. but my car also doesnt seem to run hot at all the water temp stays at 192 which i data logged with the predator.

oh and one more question are there different sound levels of pinging meaning louder or quieter cause i have heard some cars ping and its pretty loud.

it also didnt really destroy my A/F but it took a while to drop down to 13.0 at 5k the only intake part i have on it right now is teh accufab plenum. I plan on pulling the plugs tomorrow to check them out because i had an exhaust leak for about 3 months before i got it welded and it was teh same place right before the o2 sensors.(the studs were not long enough which caused the leak in the first place). Im going to try tightening it all back up again and pull the plugs and see what happens cause i dont think my fuel filter can be clogged either.