Engine Flutter with hard acceleration
I have a 2012 EB with a MBRP cat back exhaust, airaid intake, and custom tunes from MPT. Recently in my never ending pursuit of the right exhaust sound I had a shop chop my MBRP muffler off, and leave the exhaust dumped under the cab with only a resonator in place. Until I did this the truck ran like a champ, now under heavy acceleration from a stop the truck seems to make a fluttering sound from the exhaust and falls on its face until i hit approx 3300 RPM, then it takes off like a rocket ship. Any idea why its suddenly falling on its face? I contacted MPT about adjusting the tune due to the increased exhaust flow and they said it would be a negligible difference and that any adjustment would be unnecessary.