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Showing results for tags 'fluttering'.
Found 2 results
pulsates Unsmooth power on acceleration
Beagleguy posted a topic in 2014 - 2019 Silverado & SierraI have a 2018 GMC Denali 6.2 that is a month and a half old, 2300 miles, 8 speed transmission. Since new it pulsates or flutters under take off, not a miss but like something is holding it back. It seems to me a fuel management or torque converter programming issue? It just does not have a smooth pull as other vehicles I have owned do. It is smooth at level speed and has no transmission lags or jerks under acceleration or deceleration. The dealer has no answers since it does not throw a code but understands and puzzled as it is obviously there. Runs the same on 91 and/or 87 octane, literally no difference. Love the truck other than the acceleration issue, Any Suggestions Please? All update bullitons were recently verified and were been done prior to purchase/delivery.
Noise after headers install
ajmalian posted a topic in 2014-2018 Silverado & Sierra ModsHey guys, Need some help. I've got a 2016 Sierra Denali with a cold air intake,Whipple supercharger, Gibson short tube headers alongside with an aftermarket cat-back exhaust. I know I'm probably going to get roasted for the shorty headers but unfortunately long tubes are illegal where I'm from and to be very honest, I have heard long tubes with the after market cat-backs on the GM 6.2L....WAYYY TOOOO LOUD!! Coming to my issue, where I need your expertise is that there seems to be this noise from the driver's side footwell after I installed the short headers. Can't even describe whether the noise can be calleded a clicking/ticking/chattering or what, I have absolutely no idea. All I know is that it comes with acceleration. If it was a constant I wouldn't mind but it's super annoying because it's got a mind of its own. Sometimes it's not even there, then it decides to come back and even when it does, it doesn't always present itself at the same volume. Sometimes its at a soft volume, then sometimes medium and sometimes quite loud, however all the times it is with the acceleration. Most of the time it's there, it's there at a medium volume. At first I had my dealership install JBA short headers. We got this sound and my dealership claimed it was a leak. They resurfaced/machined the headers down, TWICE, changed the gasket even once, yet the sound remained. Then we changed over to Gibson short tube headers and unfortunately the same issue here too.... At the end they just gave me my truck back and said this is how short headers are and nothing can be done about it. Apparently they claim they spoke to JBA and Gibson and it seems they were told by them that it is due to the difference in size of the exhaust outlet in the engine and the inlet on the headers. I somehow don't believe my dealership because they always try to pull a fast one when they can't solve a problem. I've attached an audio file, please tell me what you think the problem could be. The dealership had my car for 43 days and after all of the fiasco above, they said whatever it is, it certainly is not a leak... so...PLEASE HELP!!!!! Voice 001_sd.mp3 Voice 001_sd.mp3 Voice 001_sd.mp3 Voice 001_sd.mp3