Cold Start Misfire on Cyl 1 and 6.

Lester · 12-04-2020, 08:17 PM

2008 135i, N54 with 80,000 km.

Runs rough for a minute or so, getting codes for misfire on cyl 1 and 6.
After it warms up, runs fine. Lots of power, no misfires.

Vanos needs servicing? I'd think plugs and/or coils would misfire after being warm.

It's never had plugs replaced, I think two of the injectors (1 and 6) were replaced under warranty early on.

Anyone else had this?

Thanks

Petro135 · 12-05-2020, 12:49 PM

I'd switch coils around and see if misfires move. Then check your plugs and gaps. Then move on from there to walnut blast Intakes, injectors

Lester · 12-14-2020, 05:56 AM

It might have been a half tank of inferior (ethanol) gasoline. I impulsively topped up with a half tank of discount 91 octane a few weeks back , and the misfires started just after that (next day). Now after a couple of refuels with Chevron 94 Techron (ethanol free) things are back to normal. Lesson learned. Codes are clean.

My baby telling me she only likes the good stuff!

NVHoo · 12-14-2020, 08:28 AM

Quote:

Originally Posted by Lester

It might have been a half tank of inferior (ethanol) gasoline. I impulsively topped up with a half tank of discount 91 octane a few weeks back , and the misfires started just after that (next day). Now after a couple of refuels with Chevron 94 Techron (ethanol free) things are back to normal. Lesson learned. Codes are clean.

My baby telling me she only likes the good stuff!

After 12 years and 80 km, it's time for new ones.

Lester · 12-14-2020, 09:27 AM

Yes, I know. If the misfires would have ramped up, I'd have gone that way. But it's running so strong, pulls great right now, I hate to change anything.

Then I'd have to make choices, which plugs, which coils, which injectors, which vanos?

I know I will eventually get there. Right now, I'm barely putting on 500 km per month what with Covid travel restrictions.

NVHoo · 12-15-2020, 08:17 AM

If you use a dealer for your repairs, check for COVID specials. Many dealers here have coupons on their web sites for 20% off service since COVID hit and cars coming in for service has substantially decreased. Alternatively, t's a pretty simple DIY job with several internet videos showing you how. Better to do it at your convenience than to have it happen again at a bad time and it likely will happen again.

Lester · 12-15-2020, 09:25 AM

Yes, I know. It's coming soon. I am concerned about a note I read on a web site about 2008 N54's having an off centre notch on the coil wires that may not be compatible with replacement coils. Has anyone run into that issue?

12-04-2020, 08:17 PM	#1
Lester Brigadier General 295 Rep 3,350 Posts Drives: Join Date: Oct 2007 iTrader: (0)	Cold Start Misfire on Cyl 1 and 6. 2008 135i, N54 with 80,000 km. Runs rough for a minute or so, getting codes for misfire on cyl 1 and 6. After it warms up, runs fine. Lots of power, no misfires. Vanos needs servicing? I'd think plugs and/or coils would misfire after being warm. It's never had plugs replaced, I think two of the injectors (1 and 6) were replaced under warranty early on. Anyone else had this? Thanks __________________ 2008 135i, Jet Black, 6 spd, Canadian Sport package, black leatherette, manual seats, aluminum glacier trim, PDC. 1983 E21 Delphin, M10, 5 speed, LSD, MSW wheels, recaro seats, Hartge strut brace, rear sway bar. [SIGPIC][/SIGPIC]
	Appreciate 0 Tweet Quote

12-05-2020, 12:49 PM	#2
Petro135 Captain 453 Rep 610 Posts Drives: 2008 135i E88 Join Date: Aug 2019 Location: South jersey iTrader: (0) Garage List 2008 BMW 135i [0.00]	I'd switch coils around and see if misfires move. Then check your plugs and gaps. Then move on from there to walnut blast Intakes, injectors
	Appreciate 0 Quote

12-14-2020, 05:56 AM	#3
Lester Brigadier General 295 Rep 3,350 Posts Drives: Join Date: Oct 2007 iTrader: (0)	It might have been a half tank of inferior (ethanol) gasoline. I impulsively topped up with a half tank of discount 91 octane a few weeks back , and the misfires started just after that (next day). Now after a couple of refuels with Chevron 94 Techron (ethanol free) things are back to normal. Lesson learned. Codes are clean. My baby telling me she only likes the good stuff! Last edited by Lester; 12-14-2020 at 06:17 AM..
	Appreciate 0 Quote

12-14-2020, 09:27 AM	#5
Lester Brigadier General 295 Rep 3,350 Posts Drives: Join Date: Oct 2007 iTrader: (0)	Yes, I know. If the misfires would have ramped up, I'd have gone that way. But it's running so strong, pulls great right now, I hate to change anything. Then I'd have to make choices, which plugs, which coils, which injectors, which vanos? I know I will eventually get there. Right now, I'm barely putting on 500 km per month what with Covid travel restrictions. Last edited by Lester; 12-14-2020 at 09:29 AM.. Reason: Typo
	Appreciate 0 Quote

12-15-2020, 08:17 AM	#6
NVHoo Second Lieutenant 161 Rep 282 Posts Drives: 2011 128i red convertible Join Date: Feb 2015 Location: Las Vegas iTrader: (0)	If you use a dealer for your repairs, check for COVID specials. Many dealers here have coupons on their web sites for 20% off service since COVID hit and cars coming in for service has substantially decreased. Alternatively, t's a pretty simple DIY job with several internet videos showing you how. Better to do it at your convenience than to have it happen again at a bad time and it likely will happen again.
	Appreciate 0 Quote

12-15-2020, 09:25 AM	#7
Lester Brigadier General 295 Rep 3,350 Posts Drives: Join Date: Oct 2007 iTrader: (0)	Yes, I know. It's coming soon. I am concerned about a note I read on a web site about 2008 N54's having an off centre notch on the coil wires that may not be compatible with replacement coils. Has anyone run into that issue?
	Appreciate 0 Quote