Hey guys I've never posted anything before so bare with me. My name is David by the way n Im new to this but I need some major advice and I know you guys have a ton more experience than me anyways I have a 2008 Mustang
GT and about 2 months ago I put axel back exhaust and last month i put an SCT SF3 programmer and JLT intake. I've been having a bad rattling noise I figured it was heat shields took them off wrapped them and noise is still there I have ruled out the full exhaust from the manifolds back and everything on the engine seems tight nothing loose... The rattling only comes when I put the car on a load! In fifth give it gas and it's super loud around 2 1/2 to 3 grand after that u can't hear it it's weird. The car doesn't get ran hard it's my daily driver! It keeps getting worse when I first heard it it was real light but now I I get on it, it's heard! I could be wrong but could it b bad gas making the valves float or maybe the butterfly on the throttle body making the noise? Please let me know if any of you guys have had this problem. My next step is to take it to ford! Oh and my car only Has 19,000 miles so it has me puzzled.