BMW 335i P0303 Cylinder 3 Misfire

SilverstoneF80 · 06-14-2017, 12:37 PM

I have a 2010 335i e90 that i purchased a few weeks ago with 100k. Was misfiring cylinder 4 and 6 so i replaced all coils and spark plugs. Those 2 stopped misfiring and now im misfiring cylinder 3. Anyone have any suggestions?

feuer · 06-17-2017, 11:18 PM

Probably injector.

Masry335i · 06-18-2017, 04:15 AM

as backwards as this sounds same exact thing happened to me. I replaced cylinder 3 again and it worked fine. Try switching coil and plugs with a known working cylinder. Dont bet on the injectors just yet!

SilverstoneF80 · 06-19-2017, 12:42 PM

The car also threw a code for bank 1 too lean and at times has white smoke coming out of the exhaust.

nsjames · 06-19-2017, 02:26 PM

Quote:

Originally Posted by ndurani3254@gmail.com

The car also threw a code for bank 1 too lean and at times has white smoke coming out of the exhaust.

that sounds very injectorish.

a simple ignition misfire isn't going to cause smoke.

the BMW manual for "customer complains of white smoke" is literally "check injectors" in the flow chart.

nsjames · 06-19-2017, 02:27 PM

http://www.e90post.com/forums/showpo...0&postcount=24

see that PDF.

it's something you need to address urgently, injector failure can cause catastrophic damage.

06-14-2017, 12:37 PM	#1
SilverstoneF80 Private 3 Rep 70 Posts Drives: 2015 BMW M3 Join Date: May 2017 Location: Brentwood, TN iTrader: (0)	BMW 335i P0303 Cylinder 3 Misfire I have a 2010 335i e90 that i purchased a few weeks ago with 100k. Was misfiring cylinder 4 and 6 so i replaced all coils and spark plugs. Those 2 stopped misfiring and now im misfiring cylinder 3. Anyone have any suggestions?
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06-17-2017, 11:18 PM	#2
feuer Major General 4277 Rep 9,209 Posts Drives: wife crazy! Join Date: Apr 2015 Location: Chicago, IL iTrader: (5)	Probably injector.
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06-18-2017, 04:15 AM	#3
Masry335i Private 14 Rep 81 Posts Drives: E92 335i 6mt Join Date: Jan 2016 Location: Toronto iTrader: (0)	as backwards as this sounds same exact thing happened to me. I replaced cylinder 3 again and it worked fine. Try switching coil and plugs with a known working cylinder. Dont bet on the injectors just yet!
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06-19-2017, 12:42 PM	#4
SilverstoneF80 Private 3 Rep 70 Posts Drives: 2015 BMW M3 Join Date: May 2017 Location: Brentwood, TN iTrader: (0)	The car also threw a code for bank 1 too lean and at times has white smoke coming out of the exhaust.
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06-19-2017, 02:27 PM	#6
nsjames Brigadier General 2443 Rep 4,330 Posts Drives: 08 328xi Touring Join Date: May 2017 Location: ohio iTrader: (0)	http://www.e90post.com/forums/showpo...0&postcount=24 see that PDF. it's something you need to address urgently, injector failure can cause catastrophic damage.
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