Help with N54 Cyl-1 Misfire Please!

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
I have posted on n54tech and have gotten great help, as well as e90post, but still havent fixed it, so I wanted to get some other input from some others. Car is stock turbos, FBO on E60. Cylinder-1 misfire is consistently at high rpm near redline and would not happen on jb4 map 1, but does on map 7. I have swapped coil packs between cylinders 1 & 2, swapped spark plugs between 1 & 2, put new NGK plugs in gapped at 0.019(95770, new 5992's) and then just yesterday put a new index 12 injector in cylinder 1, coded correctly and still the same misfire. Which really sucks because that means the injector I pulled out was fine, it was dirty, but really not nearly as bad as you would normally see. All coil pack wiring grounds are tight and have been loosened and re-seated. I am not sure what could possibly be going on. It would not let me attach a csv log from this morning when it misfired, so I put a link to the datazap log. As you can see in the log, all cylinder ignition timing look to be identical but cylinder 1 still differs from the other 5. I am at a loss here and hopefully someone here can give some insight. I have new OE Bosch plugs that I will but in this evening to see if that fixes anything at all.


https://datazap.me/u/kpdcompany/another-mis?log=0&data=1-4-11-25-26-27-28-29
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
I originally had it at 0.022 and it actully seemed a tad worse, this was on the Autolite version of plugs though, so when I put the NGK's in I gapped them at 0.019. You think opening the gap would help?
 

NoGuru

Lieutenant
Jan 9, 2018
910
372
0
Just North of Detroit
Ride
BMW 335is
I originally had it at 0.022 and it actully seemed a tad worse, this was on the Autolite version of plugs though, so when I put the NGK's in I gapped them at 0.019. You think opening the gap would help?
I don't know if it would help since you are running an Eblend.
Is this a JB4 map or MHD?
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
I don't know if it would help since you are running an Eblend.
Is this a JB4 map or MHD?

I'm running JB4 with the BMS E85 BEF. I was going to remove the jb4 completely and try an MHD Map flash only to see if it is something with the JB4. For some reason I think it is, but im not sure. I had also considered mosfet issue, but Im an 6/08 build and realoem says mine is MSD81 so I'm not sure if that could be it, especially since its only at high rpm.
 

NoQuarter

Major
Nov 24, 2017
1,545
962
0
Indiana, USA
Ride
Z4 35is, 535xi, X5 35i
there are cases where injectors where not installed properly during previous ownership where the spacer was not installed. This can cause the injector to move and make the hole wider. When the injector is installed properly later, the larger hole still is a problem and can cause a "unexplained" misfire.
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
there are cases where injectors where not installed properly during previous ownership where the spacer was not installed. This can cause the injector to move and make the hole wider. When the injector is installed properly later, the larger hole still is a problem and can cause a "unexplained" misfire.
The injector putting it in felt snug like the previous one I replaced. If this were the case wouldn't the old injector have some signs of combustion blow by?
 

NoQuarter

Major
Nov 24, 2017
1,545
962
0
Indiana, USA
Ride
Z4 35is, 535xi, X5 35i
The injector putting it in felt snug like the previous one I replaced. If this were the case wouldn't the old injector have some signs of combustion blow by?

I would assume so - unless it was more about the injector moving a bit out it's preferred orientation? So not a blow-by problem but a problem with it pointing exactly where it is supposed to be?
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
I would assume so - unless it was more about the injector moving a bit out it's preferred orientation? So not a blow-by problem but a problem with it pointing exactly where it is supposed to be?
I see what you are saying, but I feel if this was the case there would be evidence of combustion on the injector past the oring, even if it was from prior and it was hogged out some, and this was enough to cause misfiring, it would have to be enough to push some pressure past the oring don't you think?
 

filipwwa

New Member
May 17, 2018
9
1
0
Ride
M4
You have to desolder it and solder new. Simple job. Change all of them. Check and let me know... btw... there is no test in inpa

If no it could be rail presure problem. If ur fault is „misfire several cylinders, cyl1” it could be from cyl 1 to 6
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
You have to desolder it and solder new. Simple job. Change all of them. Check and let me know... btw... there is no test in inpa

If no it could be rail presure problem. If ur fault is „misfire several cylinders, cyl1” it could be from cyl 1 to 6

Code is "29CD Misfirings, Cylinder 1"

I can try the mosfets, but haven't seen many issues with the msd81. How could I track down if it's a rail pressure problem?
 

Rcboosted2007

Lieutenant
Jan 28, 2018
902
89
0
Parts unknown
Ride
07 335i
Do you misfire without e85? Do you get any other codes like cylinder injection switch off? Are valves clean/oil free, VC gasket tight, is the decoupling seal compromised. These items were not in your check list.
 

KPDcompany

Private
May 7, 2018
34
3
0
Cincinnati, Ohio
Ride
2008 335i E90
Do you misfire without e85? Do you get any other codes like cylinder injection switch off? Are valves clean/oil free, VC gasket tight, is the decoupling seal compromised. These items were not in your check list.

Honestly have not tried straight pump gas, why do you ask? I can give it a shot, but this misfire does ONLY happen on higher boost. I can run Map2 & Map5 with zero issues, but when I run Map7 it Misfires at higher RPM close to redline. I have not gotten a cylinder injection switch off code, but I have noticed that a few times when it misfires I have to restart the car or clear codes to get that Cylinder-1 to stop misfiring. Valves are clean, VCG was done a couple months ago and torqued correctly, I also recently checked torque, but can do this again. As far as the decoupling element, It was brand new with a brand new injector as I already swapped injector 1 with a new #12 before posting, all was done correctly as I have done them before with no issues. New seal & decoupler were used. I guess its possible I got a bad decoupler or something So I will check. But whats weird is I thought maybe the injector bore was enlarged from previous owner(s) but when I pulled out the old one, there were no signs of combustion blow-by past the teflon seal and no evidence of it moving around or wear.

Here are links to this mornings logs, Map2 & Map7. Map2 ran great.
https://datazap.me/u/kpdcompany/map2-no-mis?log=0&data=1-4
https://datazap.me/u/kpdcompany/map7-misifire?log=0&data=1-4
 

Rcboosted2007

Lieutenant
Jan 28, 2018
902
89
0
Parts unknown
Ride
07 335i
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