Popping noise with corsica extreme exhaust when you stand on it, 2016 mustang GT
throttle response is still stock I take it? I'm assuming this is a performance exhaust, and faster flowing. Your throttle response is too slow, you'll need to tune the throttle to the exhaust. The "popping" is usually caused by vacuum in the exhaust manifold (or headers), when atmospheric pressure is reestablished you get a pop. You can also have a too-rich fuel mix dumping into the manifold, coupled with a leak, and igniting as it comes into contact with oxygen, in fact this may be what is happening in your case because it happens on deceleration versus popping on acceleration. I suggest you tune the throttle curve and check over the exhaust for any leak.
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