Backfiring badly :(

dh58 · 06-13-2016, 09:21 PM

Anyone know what might be causing this?

I switched to NGK plugs (gapped by Justin). And it is backfiring quite bad. Very loud bang, smoke all over the road, etc.

I am running e70, with Jb4 BEF for e85, kitty dps, stage2 lpfp.

Anyone have any ideas what could be causing this? Super embarrassing and I don't have the confidence to put my foot down now.

Any ideas or suggestions? I have a log of when it happened too.

totti84 · 06-13-2016, 09:34 PM

Any logs? Mistaking it for misfiring?

titium · 06-13-2016, 09:36 PM

still got the old plugs? assuming they are oem and work chuck them back in see how you go for the 20mins or so it takes to do you've eliminated one variable. even better probably a good idea to check for codes first. CEL?

backfires are fuel burning in places it shouldn't be i.e. intake or exhaust. if you havnt got PI it's doubtful it's in the intake could be a leaking injector spitting fuel into the exaust..... have they been changed before?

dh58 · 06-13-2016, 10:26 PM

Yep i've got logs. It isn't a misfire and there are no CEL or codes.

It's definitely a backfire as there is a loud BANG then i look back on the road and there is a HUGE plume of smoke. It only happened after changing my plugs. I changed my oil too but that's pretty straight forward. It's happened 2-3 times now. Same circumstance, 2nd gear and putting foot down.

Here is the log. http://datazap.me/u/dh58/back-fire-log

Yes the injectors have been replaced but they are being a little bit squeeky on startup now. (only started happening in the cold)

Fuji · 06-14-2016, 02:43 AM

Your logs say you're running meth, is that true?

dh58 · 06-14-2016, 02:45 AM

Quote:

Originally Posted by Fuji

Your logs say you're running meth, is that true?

no... what!?

Fuji · 06-14-2016, 02:47 AM

Quote:

Originally Posted by dh58

Quote:

Originally Posted by Fuji

Your logs say you're running meth, is that true?

no... what!?

Am I going crazy?? Haha

dh58 · 06-14-2016, 02:48 AM

Quote:

Originally Posted by Fuji

Am I going crazy?? Haha

Yeah wtf..... I'm using the IOS app for the logs

Fuji · 06-14-2016, 02:59 AM

Quote:

Originally Posted by dh58

Yeah wtf..... I'm using the IOS app for the logs

Lol never mind me then.

+1 try your old plugs in and see what happens. Seems weird!

dh58 · 06-14-2016, 02:59 AM

Quote:

Originally Posted by Fuji

Lol never mind me then.

+1 try your old plugs in and see what happens. Seems weird!

old plugs are bosch, new are NGK. The old ones are pretty much done. Rough idle. There is no rough idle now.

dh58 · 06-14-2016, 03:39 AM

I've just checked again.. No settings make it think it's meth.. So I'm wondering what the meth actually means

Dackelone · 06-14-2016, 04:57 AM

So... you changed your plugs bc of a rough idle... but now your engine back fires badly.

Humm... maybe it is your plugs?

Try factory plugs bought from a BMW dealer. I've been saying for years that our cars are very sensitive to plugs.

Fuji · 06-14-2016, 05:00 AM

Quote:

Originally Posted by dh58

I've just checked again.. No settings make it think it's meth.. So I'm wondering what the meth actually means

That's really weird man!

vtl · 06-14-2016, 05:37 AM

Regap your plugs, you said you bought them pregapped?

The NGKs you have to bend the ground tab a LOT to get it to 0.022" because the gap is so wide. After its been bent that much it doesnt take much force at all for the gap to open up and be out of spec.

Pull the plugs, check the gaps. Careful with the electrode because it is very brittle and can be damaged easily.

froop · 06-15-2016, 01:13 AM

Do you have NLS setup by any chance?

When I turn NLS on in my car (Procede) the backfires are beyond loud. I fucks up rev match downshifting though so you can't run it on the circuit, only really for the drags.

dh58 · 06-15-2016, 01:48 AM

Thanks guys.. I pushed her hard today in the same circumstances as before with no issues. I can't check out the plugs until the weekend.

I don't have NLS.

I got the plugs pregapped by Justin at Advan so I'm pretty confident that they are good. However I will be taking them all back out to check.

dh58 · 06-17-2016, 06:48 AM

Very weird... the first 2 days after the change, backfires were easy occurrences.. I have tried everything in my will to make it happen again over the past few days and nothing..

So could this be due to anything during the change of the spark plug? And not the spark plug them selves.. ?

Fuji · 06-17-2016, 10:41 PM

Did you notice anything falling past the plugs when you removed them? something may have been burning off?

dh58 · 06-18-2016, 06:48 AM

Quote:

Originally Posted by Fuji

Did you notice anything falling past the plugs when you removed them? something may have been burning off?

Yes oil. It was in plugs 2-4 i think from a previous oil change where i spilled it.

06-13-2016, 09:21 PM	#1
dh58 Major 108 Rep 1,075 Posts Drives: 135i Join Date: Aug 2010 Location: Bunker in Sydney iTrader: (1)	Backfiring badly :( Anyone know what might be causing this? I switched to NGK plugs (gapped by Justin). And it is backfiring quite bad. Very loud bang, smoke all over the road, etc. I am running e70, with Jb4 BEF for e85, kitty dps, stage2 lpfp. Anyone have any ideas what could be causing this? Super embarrassing and I don't have the confidence to put my foot down now. Any ideas or suggestions? I have a log of when it happened too.
	Appreciate 0 Tweet Quote

06-13-2016, 09:34 PM	#2
totti84 Major 112 Rep 1,140 Posts Drives: N54 135i 6MT Join Date: Aug 2014 Location: Sydney, Australia iTrader: (5) Garage List 2009 BMW 135i M Sport [0.00]	Any logs? Mistaking it for misfiring?
	Appreciate 0 Quote

06-13-2016, 09:36 PM	#3
titium Major 327 Rep 960 Posts Drives: 2009 BMW 135i Join Date: Jun 2015 Location: Sydney iTrader: (0)	still got the old plugs? assuming they are oem and work chuck them back in see how you go for the 20mins or so it takes to do you've eliminated one variable. even better probably a good idea to check for codes first. CEL? backfires are fuel burning in places it shouldn't be i.e. intake or exhaust. if you havnt got PI it's doubtful it's in the intake could be a leaking injector spitting fuel into the exaust..... have they been changed before?
	Appreciate 0 Quote

06-13-2016, 10:26 PM	#4
dh58 Major 108 Rep 1,075 Posts Drives: 135i Join Date: Aug 2010 Location: Bunker in Sydney iTrader: (1)	Yep i've got logs. It isn't a misfire and there are no CEL or codes. It's definitely a backfire as there is a loud BANG then i look back on the road and there is a HUGE plume of smoke. It only happened after changing my plugs. I changed my oil too but that's pretty straight forward. It's happened 2-3 times now. Same circumstance, 2nd gear and putting foot down. Here is the log. http://datazap.me/u/dh58/back-fire-log Yes the injectors have been replaced but they are being a little bit squeeky on startup now. (only started happening in the cold)
	Appreciate 0 Quote

06-14-2016, 02:43 AM	#5
Fuji Lieutenant 96 Rep 577 Posts Drives: SGM E92 335i Join Date: Oct 2013 Location: Melbourne, Victoria iTrader: (0)	Your logs say you're running meth, is that true? __________________ SGM E92 335i FBO [COLOR="Indigo"]/ MHD Stage 2 Plus / CP-E FMIC / DCI / VRSF DP / VRSF CP / Turbosmart Raceport BOV / BMW PE / H
	Appreciate 0 Quote

06-14-2016, 03:39 AM	#11
dh58 Major 108 Rep 1,075 Posts Drives: 135i Join Date: Aug 2010 Location: Bunker in Sydney iTrader: (1)	I've just checked again.. No settings make it think it's meth.. So I'm wondering what the meth actually means
	Appreciate 0 Quote

06-14-2016, 04:57 AM	#12
Dackelone European Editor 10528 Rep 22,992 Posts Drives: N54 e82 Join Date: Feb 2010 Location: Bayern, Germany iTrader: (1)	So... you changed your plugs bc of a rough idle... but now your engine back fires badly. Humm... maybe it is your plugs? Try factory plugs bought from a BMW dealer. I've been saying for years that our cars are very sensitive to plugs. __________________ Dackel's European Delivery Museum Guide
	Appreciate 2 Quote

06-14-2016, 05:37 AM	#14
vtl Brigadier General 1493 Rep 3,148 Posts Drives: 2008 BMW 135i MT Join Date: Apr 2015 Location: Melbourne, Australia iTrader: (0)	Regap your plugs, you said you bought them pregapped? The NGKs you have to bend the ground tab a LOT to get it to 0.022" because the gap is so wide. After its been bent that much it doesnt take much force at all for the gap to open up and be out of spec. Pull the plugs, check the gaps. Careful with the electrode because it is very brittle and can be damaged easily. __________________ Build Thread
	Appreciate 0 Quote

06-15-2016, 01:13 AM	#15
froop Colonel 171 Rep 2,682 Posts Drives: 08 AW 6MT E82 Join Date: Jul 2012 Location: Sydney, Australia iTrader: (3)	Do you have NLS setup by any chance? When I turn NLS on in my car (Procede) the backfires are beyond loud. I fucks up rev match downshifting though so you can't run it on the circuit, only really for the drags. __________________ froop's AW 135i Build Thread
	Appreciate 0 Quote

06-15-2016, 01:48 AM	#16
dh58 Major 108 Rep 1,075 Posts Drives: 135i Join Date: Aug 2010 Location: Bunker in Sydney iTrader: (1)	Thanks guys.. I pushed her hard today in the same circumstances as before with no issues. I can't check out the plugs until the weekend. I don't have NLS. I got the plugs pregapped by Justin at Advan so I'm pretty confident that they are good. However I will be taking them all back out to check.
	Appreciate 0 Quote

06-17-2016, 06:48 AM	#17
dh58 Major 108 Rep 1,075 Posts Drives: 135i Join Date: Aug 2010 Location: Bunker in Sydney iTrader: (1)	Very weird... the first 2 days after the change, backfires were easy occurrences.. I have tried everything in my will to make it happen again over the past few days and nothing.. So could this be due to anything during the change of the spark plug? And not the spark plug them selves.. ?
	Appreciate 0 Quote

06-17-2016, 10:41 PM	#18
Fuji Lieutenant 96 Rep 577 Posts Drives: SGM E92 335i Join Date: Oct 2013 Location: Melbourne, Victoria iTrader: (0)	Did you notice anything falling past the plugs when you removed them? something may have been burning off? __________________ SGM E92 335i FBO [COLOR="Indigo"]/ MHD Stage 2 Plus / CP-E FMIC / DCI / VRSF DP / VRSF CP / Turbosmart Raceport BOV / BMW PE / H
	Appreciate 0 Quote