jmattav i

My new 2017 Stingray backfires during a hard acceleration in the "sport" and "track" modes. It doesn't happen during the other 3 modes. Has anyone else experienced this behavior?

vbdenny

Why yes I have. Barks at you under WOT.

owc6

It is not a backfire , but a microsecond cutoff of fuel to facilitate a quicker gear change.

Music to the discerning ears!

hangman

Beautiful music to my ears.

Power Hawk

Perfectly normal and I really like it. First time it happened to me it put quite a smile on my face.

Foosh

It also occurs in Tour mode during hard acceleration, but I have my NPP set to open valves all the time.

bjones7131

Noticed it on my 16 stingray but not the 17 GS, go figure.

jmattav i

Thanks to all who replied to my inquiry. Just like the noise of a diesel engine is the sound of economy, the burb of the Vette engine is the sound of power. I did uncover a GM service bulletin from March 17, 2017 that states "the pop or backfire sound heard while performing a wide open throttle maneuver while in the Sport or Track modes is normal". While the bulletin doesn't give the cause, your explanation of a very brief fuel cutoff makes a lot of sense. Thanks again.

Jim

davepl

And for the curious, this should only happen on the A8 of course... M7 has no-lift-shift but doesn't do the fuel cut.

owc6

It happens with the A6, too.

redman76

My 17 GS M7 does it. Took one of my son's friends for spirited drive and it popped during 1-2 shift. Sounded amazing. I'm sure it left an impression on him too.

Hopper12

Replaced the X pipe over the weekend without the 2nd cats, and the bark is even better. Love it.

1 HOT 07

Love the "bark" it is the sound of power. :-0

2kvetmy

my grandpappy,who was a Chevy carburetor mechanic during the 40's,50's,and, 60's, ajways told me that a backfire was not good on an engine,and, those engines did not have the hp that our Vettes have.
Matter of fact, I have seen mufflers and exhaust pipes blow off from a backfire.

davepl

It's not a backfire anyway. A "backfire" is through the induction system, whereas this is out the exhaust.

What your grandpappy was talking about is a transient ignition loss. Take a 1969 Nova, drive it 30 mph, turn they key off, coast 5 seconds, turn it back on: BOOM. Kinda fun when you're a kid. I used to do it in underpasses to scare bicyclists (30+ years ago, mind you, and not a proud memory). But it can blow up mufflers and exhaust quite easily.

That's the excess fuel accumulated in the exhaust system. Because this is a fuel cut, it's the exact opposite and cannot cause the problem you're thinking of.

Grandpappy would love it, I'm sure.

a66bbvet

Mine backfires at 6000 rpm under a load. It happens when I am driving along at 40 - 50 mph and kick down on it. It shifts down and goes to 6000 and backfires. Trouble is the cars shifts at 5500 when I accelerate from a start. In my mind the car should not have gotten to 6000 as it should have shifted gears at 5500. I have it scheduled at dealership Thursday.

vbdenny

When you hear the third shift bark, it's time to hang on. One of the more pleasing aspects of the automatic.

trivette

Mine is an early C7 and when I first experienced the 'bark' I wasn't sure what was going on. There were others on the forum at that time commenting as well and it was eventually concluded it was normal. It hadn't been something happening on the C6's as far as we knew so it was a new experience that we grew to appreciate!

6spdC6

That small "backfire" is a nice thing to listen to. If it happens with a friend in the car they normally tell me something wrong with your car. I then explain it and they then understand.

Where I live on the large lake we have very few passing zones and in the summer slowpoke drivers gawking at the scenery so If you get a chance to pass, got to take it or hang there behind the slow mover sometimes for a lot of miles. You time it right and the backfire will hit right as you go by them, it does tend to wake them up.

trivette

I did exactly that coming home from Road America on Sunday.