Slight backfire/sputtering when decelerating

[carfansince73]

I haven't had a manual trans car for a long time. When I am coming to a stop with the car in gear and the clutch out, the car will backfire/sputter a little around say 10mph. It doesn't sound bad to me, but I was just wondering if anyone else was hearing this.

[Crowley]

Does this happen all of the time or just when the engine / exhaust is cold?

Crowley

[Vash]

Is that how you normally come to a stop or your just testing using the gears to slow you down? It should be clutch in when your decelerating unless you specifically want to use the tranny to help slow you down. And the backfire is probably normal. It would of tossed code (ck eng light etc) probably is something was wrong with the ignition.

[carfansince73]

Originally Posted by Crowley

Does this happen all of the time or just when the engine / exhaust is cold?

Crowley

All the time really. It's not really loud by any means, but I can hear it inside.

[carfansince73]

Originally Posted by Vash

Is that how you normally come to a stop or your just testing using the gears to slow you down? It should be clutch in when your decelerating unless you specifically want to use the tranny to help slow you down. And the backfire is probably normal. It would of tossed code (ck eng light etc) probably is something was wrong with the ignition.

I usually always leave it in gear when I know I'm going to come to a stop. I let the engine help slow me down, kind of like in an automatic where the engine helps slow you down until the torque converter unlocks at low speeds.

Yeah, no check engine lights either. I'd say it's normal, and it really doesn't bother me. Just wondering if anyone else heard it when decelerating in gear at low speeds.

[lnsjr1]

Its a LS thing , I have had 2 over a 6 year period. They all do it.

[beowulf80]

I've found the same thing, worse when the car is cold. As you said, this only happens with the clutch out, so you are basically engine braking.

The poping you are hearing is most likely the pressure build up inside the cylinder escaping into the exhaust. Its debateable if this is really bad for your engine; given the very low amounts of power I would doubt it. It is more common to use engine braking on diesel engines, which by the nature of the combustion process are made to handle much, much higher BMEP's. Nonetheless I find it semi-annoying, so more often than not I've been shifting it into neutral early and coasting it down. You'd be surprised how long you can coast with little to no loss in speed, plus it saves you some fuel.

Forgive me for linking Wikipedia, but its got a decent explanation:
http://en.wikipedia.org/wiki/Engine_braking

[nards444]

mine does the same.

[BOBSS]

I have ARH headers now with electric cutouts, you should hear this spit n pop
Of course it's in true stereo now, I love it. I think it's unburned fuel hitting the headers in the primaries. The car is running rich and with a tune it should improve. I hope it doesn't go away for good

[carfansince73]

I was pretty sure it was normal and not bad in any way. Still good to hear others have it and are not worried either.

Like I said though, it's not a bad sound either.

[franknbeans]

this is the extra fuel burning off and popping when you slow down.. . very normal.

[badkarma]

Hope it's not bad for the engine, cuz I do it on purpose coming downhill in my subdivision so all the morons can hear and not back out in front of me.

Plus it scares prudish women and small children.

[djsnoflake]

I have that sound, and I love it!

Mwahahahahaa!

I love that some of the exhaust vids showing up seem to amp it up a bit. I like to think of it as my Camaro showing its' dislike for other cars. Mostly those silly import boys.

[Gentry78]

very normal its just the extra fuel and compression of the cylinders which is good for the engine because it actually helps clean it out some

[14pilot]

When you completely get off the gas pedal and are decelling, the fuel management shuts off the injectors to save fuel and to help pass CAFE requirements. Tuning can add some fuel when the throttle is in this closed position to reduce the decell popping noise.

Driving style can reduce the popping too. While down shifting and decelling, try giving the engine some fuel with your right foot. The injectors come back on when the pedal is pushed and the engine's RPM can be matched to the decell situation to smooth things out.

[CamaroHutch]

my LS3 does the same thing! I love that sound...

[ffrcobra_65]

That is just your car's way of telling you "why the F$%* are you slowing down?!!?"

[MerlinZero]

Originally Posted by carfansince73

I haven't had a manual trans car for a long time. When I am coming to a stop with the car in gear and the clutch out, the car will backfire/sputter a little around say 10mph. It doesn't sound bad to me, but I was just wondering if anyone else was hearing this.

I hear it all the time. I love the overrun on this car... sounds sooooo beastly.

[RuggZ]

Ah, yes. I call it 'the dragon spit'

you understand she must sound her call to intimidate 'the heard'

We are so lucky to have a car like this

Chevy Love
GM Rocks

[TAG UR IT]

Slight?...

Dude..you GOT to hear mine!!!!!!

[zebra]

i do it in the truck every now & then just for kicks & giggles. it's a normal thing, but i don't know why on earth you'd do it all the time. if you know you're coming to a stop, it's much easier on the car & saves gas to put in neutral & coast. also, one thing to remember - brake pads are much cheaper to replace than driveline components, so why put that extra stress on them if it ain't necessary? if you're coming to a turn at the track (or making ricer kids p*** themselves), it's a great idea to engine brake, but for driving to work, not so much. just my .02

[BOBSS]

I wonder, with headers, if the popping, some of which can be pretty loud, would be picked up by the knock sensor(s), (assuming there is one) and retard the timing, thinking it's detonation...?

[Gentry78]

Originally Posted by BOBSS

I wonder, with headers, if the popping, some of which can be pretty loud, would be picked up by the knock sensor(s), (assuming there is one) and retard the timing, thinking it's detonation...?

wouldn't really matter he's coming to a stop

[CamaroHutch]

Originally Posted by zebra

i do it in the truck every now & then just for kicks & giggles. it's a normal thing, but i don't know why on earth you'd do it all the time. if you know you're coming to a stop, it's much easier on the car & saves gas to put in neutral & coast. also, one thing to remember - brake pads are much cheaper to replace than driveline components, so why put that extra stress on them if it ain't necessary? if you're coming to a turn at the track (or making ricer kids p*** themselves), it's a great idea to engine brake, but for driving to work, not so much. just my .02

Does it use extra gas? Does it really add strain to the drivetrain? I have owned many MT vehicles and used engine breaking on everyone. Never had an issue. I would assume its using the same amount of gas as at idle (but I honestly am not sure).... I mean, 18 wheelers do it all the time (they sort of have to, or they just lose their brakes)