What is Backfiring ??

[TitanRev]

When backfire happen. Does black smoke comes with it also ?

 

[SkYwAlKeR]

my friend can do misfiring/backfire on purpose... method??.. rev ur engine till almost redline, quickily switch off ur ignition key till u hear da sound "POP!!"... looks cool but it will spoil ur car engine...

doing it while normal driving??... never experience it before coz i never rev high high...
but the other day when i was coming down from genting, i used 3rd gear and rev about 3000rpm downhill... constantly can hear those popping sound coming out from my exhaust... (of coz when i'm driving, i not sure got fire come out or not)... my friends said its because of sparkplug problem... but till now i havent changed my plugs and they work still fine...

 

[fritz]

Hm..will it spoilt ur engine? If im not mistaken..almost all 4age 20v kaki also got back fire wen changed to direct piping woh..for the same case..my car also will "pop" wen rev till 6K-7.5K rpm and shift gear. As for those plup plup plup sound..it occurs wen release throttle very slowly..btw..im driving bt 20v..should be ok gua..
And yes..after pop..black smoke will come out..

 

[escaflowne]

Titanrev bro,i suppose your mixture is too rich.Try to check for your a/f ratio and set it lean abit and see will it backfire again.

 

[white_bird]

agree.. it happens when ur afr too rich or ur spark plug isnt good oredi~ mayb check ur plug first.. if the colour of the tip is black n wet it can be too rich A/F mixture..

 

[howiechoo]

if caburator engine, the pop pop sound when u release throttle is normal...
but for efi, i think ur fuel misture too rich..

 

[cyclonite]

backfiring = exhaust comes out from air intake instead of exhaust pipe

reason? for some reason the intake valve was left open during exhaust stroke. broken timing belt? cams? valve springs?

 

[madpilot]

Dun care a lot lah... for those engine old enurff one... is kewl to have dat kind of sound.. for new like 206.. better send her back for check.. send to the manufacturer..or write to them all this symptom... :rolleyes:

 

[TitanRev]

BUt, when my go the boom sound no black smoke come out woh. Maybe i will have the plug check. If the plug is normal then can confirm is AF too rich rite ?

Why so weird wan. I changed the exhaust system then this sympton happens but when i mood my Atos or Unser nothing like this happens ?

Can it be like this. Maye my car ori setting is a bit rich. But be4 the CAT was taken out the fuel is filtered inside the CAT so no fuel is passing out to the exhaust so when i took out the CAT extra fuel can travel to the mufler so this problem happens ? Can it be ?

 

[zan]

shudnt remove the CAT in my opinion. normally catalytic coverter has a sensor to detect whether fuel completely burnt or not, if not complete burnt then most probably mixture too rich. so, ECU will adjust the mixture to appropriate level.

the sensor is known as CO sensor, also oxygen sensor. if i am not mistaken.

 

[boggysv]

Can it be like this. Maye my car ori setting is a bit rich. But be4 the CAT was taken out the fuel is filtered inside the CAT so no fuel is passing out to the exhaust so when i took out the CAT extra fuel can travel to the mufler so this problem happens ? Can it be ?

OMG..your cat filters fuel!!!! OMFGHi2SuperCAt!!!!

You sir, just need to learn how various exhaust sensors work. That is one of the main objectives/advantages of EFI.

btw, please put back the catalytic converter....think of all the pussies that died from your exhaust smoke. Or at least get a high-flow cat, costly, but at least enviromental friendly..

 

[TitanRev]

I'm using a block bullet now. Is that consider a High flow CAT ?

 

[Pickcell]

Get a Persian Cat.. Very friendly and.. errr.... :vroam:

 

[TitanRev]

Get a Persian Cat.. Very friendly and.. errr.... :vroam:

Haiya...I'm refering to Cataylic Converter lah. Not the Miao Miao cat...:secruity:

Just sent my car for checking. All my spark plug is great. Means AF is fine...Suspect is the bullet problem..

 

[FoarGeez]

i got dat 2 'problem'.. my previous car, saga (a) 1991. i changed bigger bullets n bigger muff.. then my fren claim got bluish, sumtime orange fire came out n been sucked in back.. happened when i alwez drive abv 120 n release d accelerator.. scared ler.. any bros here know y..

 

[SkYwAlKeR]

i experience driving on highway about 120kmh... when u suddenly release the gas pedal, the car like jerks a little and the exhaust note is louder than u slowly releasing ur gas pedal... is this sign of my exhaust is sucking in air after i suddenly release my gas pedal???