Misfires on 4,5, and 6 under load

thelamp · 08-19-2023, 09:57 PM

About a week ago I noticed that when I do a pull in really any gear around 5k RPM the car will miss bad and throw a check engine light. MHD and ISTA show misfires on 4,5, and 6 and I have no idea what would be causing this. I've switched tunes, swapped around coils and plugs, nothing changes. All injectors are index 12s which makes me doubt its that. Car runs fine if I just drive it normally or do slight pulls but anything full throttle pops a CEL. Also pulled my DME and its a MSD81, with a multimeter the mosfets are all fine. My last idea is it being a bad O2 sensor which I'm hoping not because it's going to be a pain to get to.

I have a log from a 3rd gear pull:
https://datazap.me/u/gabezim/bank-2-...14-15-21-22-23

If anyone has an idea or a similar issue I'd appreciate the help

twinturbovan · 09-07-2023, 04:01 PM

What coils do you have?

thelamp · 09-18-2023, 12:54 PM

Quote:

Originally Posted by twinturbovan

What coils do you have?

Eldor coils, however misfire doesn't follow when changing coils around

twinturbovan · 09-19-2023, 03:26 PM

Hmm.. thats weird. I had misfire issues for years and turned out to be bad R8 Coils. All my misfire issues are gone with the B58 setup. What plugs are you using?

08-19-2023, 09:57 PM	#1
thelamp Registered 0 Rep 4 Posts Drives: 2011 335i Join Date: Sep 2020 Location: Wisconsin iTrader: (0)	Misfires on 4,5, and 6 under load About a week ago I noticed that when I do a pull in really any gear around 5k RPM the car will miss bad and throw a check engine light. MHD and ISTA show misfires on 4,5, and 6 and I have no idea what would be causing this. I've switched tunes, swapped around coils and plugs, nothing changes. All injectors are index 12s which makes me doubt its that. Car runs fine if I just drive it normally or do slight pulls but anything full throttle pops a CEL. Also pulled my DME and its a MSD81, with a multimeter the mosfets are all fine. My last idea is it being a bad O2 sensor which I'm hoping not because it's going to be a pain to get to. I have a log from a 3rd gear pull: https://datazap.me/u/gabezim/bank-2-...14-15-21-22-23 If anyone has an idea or a similar issue I'd appreciate the help
	Appreciate 0 Tweet Quote

09-07-2023, 04:01 PM	#2
twinturbovan Second Lieutenant 207 Rep 223 Posts Drives: 2009 BMW 135i M Sport Vert Join Date: Jun 2019 Location: San Antonio, TX iTrader: (0)	What coils do you have?
	Appreciate 0 Quote

09-19-2023, 03:26 PM	#4
twinturbovan Second Lieutenant 207 Rep 223 Posts Drives: 2009 BMW 135i M Sport Vert Join Date: Jun 2019 Location: San Antonio, TX iTrader: (0)	Hmm.. thats weird. I had misfire issues for years and turned out to be bad R8 Coils. All my misfire issues are gone with the B58 setup. What plugs are you using?
	Appreciate 0 Quote