hi guys and gurls i got about 590kms on my car im noticing when gearing down to a light or slowing down im noticing some backfire from my exhaust is this normal, im bringing it tomorrow to the dealer

 

is it a definite backfire? or is is just cuz ur downshifting? did u break the car in right???

 

I dont think it's a problem... Mine does it too... It's normal... Actually sounds kinda cool... I small back fire.... pop pop popopop lololol something like that!!... All depends on how fast I am going and then down shifting or from what RPM's to what LOWER RPM's I'm going while down shifting!

 

yea, some cars sound like that when they downshift

 

SRT-4's do it

 

my WS6 TA with the 6 speed does it as well

 

welll yea its a backfire but why is it doin that

 

a lot of cars do that when u downshift. i dont think its anything bad, but its tough to tell without seeing the car, see what the dealership says

and i hope u dont downshift to a stop! its bad for the car

 

well i had a integra gsr and never had backfire and also a 2002 infiniti g20 no backfire, i have been driving standards since i was 17 im now 28

 

i dunno what to tell u. some cars do it, some dont, ive driven cars that do, and dont

 

well we see what the dealer thinks, the car is awsome i will break in at 1000km forgot to mention the p-zero tires list here at 579.99 and most places here sell at 375 -385.00

 

doesnt sound normal to me at all...Ive driven four different cars and never had one backfire...can someone name me what cars backfire as a normal daily basis

 

The cars that tend to "backfire" or "pop" during downshifting or deceleration are usually high-performance vehicles with low-restriction exhausts. High-performance 4-cylinders tend to do it the most. Examples of cars that "pop" under deceleration are the Dodge SRT-4, Subaru WRX/STi, Mutsubishi Evo, Acura RSX, and apparantly the Cobalt SS S/C.

Its nothing to worry about really. If you really can't stand the popping, it can be eliminated by installing a resonator in the exhaust system, but it doesn't really bother most people

 

From my knowledge and experience, most of the poping that you hear is the excess fuel in the combustion chamber or already on its way to the headers. This fuel is being ignited by the hot walls that are in those areas. It occurs on down shifting because the throttle is closed but the fuel is still being dumped into the system because of the revs on the engine.

It really doesn't do any damage to the engine, and besides I think it sounds pretty cool too. Well there's my 2 cents, hope it was useful.

 

ok so the ping'ing noises that i hear after i shut the car off is normal?

 

It could be all the metal bits cooling down. My S10 used to do it ALL the time.

 

Wesmanw02 nailed it on the head. nothing to be alarmed about. it's just because you have a larger exhaust pipe diameter to accomodate the supercharger at high RPM under boost. This means under normal decelleration you'll get some popping. it's detonation and nothing to be concerned about since it's too far back in the exhaust to hurt anything in the motor. My friends 500HP Camaro does it when we pass the traps at the strip or off the gas on the freeway. 2x 3" w/ cutouts and it has a supercharger as well. Just a loss of backpressure.

Philco....that's not great. that's a timing issue and when you park it and shut it down and it pops that could be two things. try upping your octane and if that doesn't work, get your ECM reflashed. The cars I work on do that when we have to much timing in them or it's 100+ degrees outside..

 

back when i owned my '02 Camaro Z28 6-speed, it always backfired at low speed downshifts. it only had 20,000 miles on it. the Cobalt SS des it because of boost i beleive

 

Basically anything funny from exhaust just dont worry cus u may hear pops one day then bangs or knocks (heat discipation) knocking will scare ya just remember if you were driving the whip like a race car then , turn back into the conventional motorist the vehicle has to also

 

Gumby is right in what is happening when a car backfires. Every car (ecspecially with a manual) backfires when slowing down in a low gear, or downshifting. The thing is that most stock exhaust have enough back pressure and sound absorbtion material that you won't hear it.

The big reason you hear a backfire is due to the low restriction exhaust. My alero I could never a sound when downshifting until I put on a 2.5" catback magnaflow muffler. Then everytime I downshifted I would hear *pop pop pop pop pop*

The alero had an ecotec so it must be an ecotec property to have louder then usual downshift pops

 

Thats the catalytic converter cooling off.

 

Dosent that backfire A LOT when u downshift????

 

Keep in mind that the SRT-4 has no muffler....

 

Careful guys. What you're describing is NOT backfiring. It's called AFTERFIRING.

Backfiring is when the unconsumed fuel creeps back up into the intake tract, and ignites IN THE INTAKE MANIFOLD. It's VERY harmful.

Afterfiring is actually what's being described here, when unburnt fuel in the EXHAUST SYSTEM ignites. It's generally harmless, and generally experenced on most cars with extremely free-flowing exhausts, like the ones mentioned.

Afterfiring in your SS is okay, and probably even expected. Backfiring is not.

 

no but the srt-4 has two resonators, the srt-4 especially with the stage one upgrade pop like mad on the downshift, im sure quite louder than the ss. its normal just unburnt fuel touching off in your exhaust pipes