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Posted

Hello:

2017 Sierra rapid backfire in exhaust at light throttle and any speed under 8 cyl or 4 cyl I read something about this before but I cannot find it now

Posted
Hello:
2017 Sierra rapid backfire in exhaust at light throttle and any speed under 8 cyl or 4 cyl I read something about this before but I cannot find it now
I would scan it but first thing in my mind is maf.

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Posted

Thanks 1slow1500 I will probably take it to the dealer my fear is that they won't be able to duplicate the problem. It sounds like popcorn popping in a microwave

Posted
Thanks 1slow1500 I will probably take it to the dealer my fear is that they won't be able to duplicate the problem. It sounds like popcorn popping in a microwave
Is there a aftermarket intake or exhaust.

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Posted

Yes a cat back Gibson single pipe exhaust but it has been on there for over a month before this popping started. Do you think a better grade of gas could fix this?

 

Posted
Yes a cat back Gibson single pipe exhaust but it has been on there for over a month before this popping started. Do you think a better grade of gas could fix this?
 
What I was getting at is af tables are off. Is that a cat back or is it more? Factory is rich so there in a after fuel. I would pick a tune an leak it out some. Better mpg and no pop.

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Posted
What I was getting at is af tables are off. Is that a cat back or is it more? Factory is rich so there in a after fuel. I would pick a tune an leak it out some. Better mpg and no pop.

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Dame af and less back pressure is back fire.

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Posted

I'm not sure I'm understanding what you are saying, do you mean that less back pressure is causing the popping and I need a tuner to fix the mixture?

 

Posted
I'm not sure I'm understanding what you are saying, do you mean that less back pressure is causing the popping and I need a tuner to fix the mixture?
 
That's what I think based on my truck I just cut the muffler and resonator and it would back fire. I looked at the factory tune and it was rich. I leaned it out and most of it was gone.
Also see it is is when it goes to V4 mode. My truck sounds like a ricer car and it louder than V8 mode. So I deleted that also.
A cone is about $90 And a augur is $20.

You should tune it anyways to get the best power,mpg, or driveablity. Best mod to any car really. b50117621dd7dc3431463a86f95b2ae8.jpgbacceb0bed8e8537485703bc50ddca3e.jpgc39568612d7be0ec5409fed1aaaa7d5f.jpg

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Posted

What will a tune do to my warranty? I don't want to screw that up. I did find another potential problem this being a slight exhaust leak at the ball flange right behind the cat, the ball clamp is as tight as it can go metal to metal completely tight. I think the ball flange on the head pipe that came with the cat back system was not formed properly and I'm wondering if under the conditions that popping happens air/oxygen is getting into the exhaust pipe and igniting sunburned fuel.

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