I just recently got headers for my truck and it has been shifting fine for a month until now. When ever im on the hwy at 70 mph i hear this knocking noise that i never heard before. It sounds like a train on the train tracks going fast and its scaring the daylights out of me.

The knocking ocurs at 70 mph, but before or after there is no knocking. Off the line from stop to go, it feels like the truck has lost some power. Ive change the tune to stock and its still the same.

Had recently changed coil and spark plugs, cleaned throttle body but that was a year ago.

Here is the data that i recorded maybe you can check it out and maybe help me solve this problem. Thanks

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Missfire.efi
TCC Lock Up On 4th_0001.tun