I've got a C7, Z51, exhaust , and it's an automatic. When I'm accelerating hard, just before a shift, there's a pop that is very noticeable. I've tried to go through the gears manually and the same pop just as I'm going into the next gear. I'd like to hear from anyone that has the same sounds I do, or a mechanic that could explain it.
Engine noise
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Interesting I hear it is normal? My neighbor has a coupe auto and his does not pop? is this a z51 thing only or both models? If both why does his not pop?
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Dependent on how hard you are stomping on the gas not related to base vs Z51.
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Yes my neighbor stomped on the gas, he likes to race with other cars on the streets and no pops from his c7?
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Does he have the NPP and is it set to "off" or non-linked to drive mode? RedHot pops pleasingly
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he does not have npp, that may be the clue to being normal?Does he have the NPP and is it set to "off" or non-linked to drive mode? RedHot pops pleasingly
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Right on the money.
Need a tech here, it has to do with the gas loading up prior to a hard shift and then igniting, I'm not a tech so this may be wrong but I think it does it on all a6's, not exhaust dependent......mark should know?
See comment from zl1 here, I've read it more than once in a couple places:
http://forums.corvetteforum.com/c7-general-discussion/3403169-pop-and-max-rpm-shifts.html
See comment from zl1 here, I've read it more than once in a couple places:
http://forums.corvetteforum.com/c7-general-discussion/3403169-pop-and-max-rpm-shifts.html
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I would like to have this verified by someone like the Ron Fellows driving class that i plan to attend sometime towards the end of this year or in Jan 2015? If there are any students going in the near future maybe they can verify this and then post their finding?
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I think you place a lot more faith in the knowledge of the Ron Fellows instructors than is warranted as this is the 2nd or 3rd time you have mentioned this. If you believe this is a problem your solution lies with your dealer and GM Customer Service.
On this issue it's programmed in the fuel management as it momentarily kills ignition while still operating the fuel injectors. This causes a small amount of unburnt fuel to pass through the cylinder and light off when it hits the hot exhaust. It can be tuned out with the ECM but it's been reported it was left in to mimic the sequential shifter on the race car.
Bottom line, it's normal but it doesn't always happen.
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You're right, you don't get it....on a full on A6 acceleration, AFM is no where involved...
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We have AFM so we can have a 460hp sportscar. Without the MPG these features provide GM would not produce the Corvette in volume due to CAFE regulations but we are drifting off topic.
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Although I own spoons and shovels and spades, I only eat my cereal out of a spoon.
I also do not use a sledgehammer to mount a picture on the wall.
It is nice to have all the fun tools, but it doesn't make sense to use something inefficient when it is not needed.
Wow, I just got home so I thought I would see if anyone replied to my question of a pop while shifting under hard acceleration. 16 fellow Vette owners chimed in. This is so cool to have this forum to get input on any issue. Thanks gentlemen...
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