[kevinb21]

This car is really just making me question my sanity here, 2010 BMW 335i coupe n54, spun a rod bearing so I put in a new n54 with upgraded rod bearings and it had a whole bunch of misfires and nonsense. Changed the plugs with colder ones, changed all 6 coils with Delphi, changed all 6 injectors with index 12 and most recently I bought a Brand new oem bmw HPFP and low pressure fuel sensor. The car KEEPS MISSFIRING. It is full bolt on MHD stage 2+ with chargepipe, downpipes, tial bov, and a FMIC. im running v9.0 mhd stage 2+ and every single time I go hard on the gas the car goes hard but not nearly as fast as my friends tuned n55 335i. The codes I am getting this time are
Cylinder 2 misfire
cylinder 4 misfire
cylinder 6 misfire
2C32 Lambda Control 2

This morning it also threw a 30ff.

Here is my log from this morning after changing the HPFP
https://datazap.me/u/kevinb21/may-29?log=0&data=21-26

its clear I am missing boost and my wastegate rattle is god awful so I know I need to adjust them and do the "temp fix"

other than that What seems to be the issue? btw, im aware the car has downpipes but it still has secondary cats but it smells baddddd, kinda like a toyota i had with a bad o2 sensor. And it gets 9mpg. BAD.

Previous thread(s)
https://www.e90post.com/forums/showt...6#post27577456
https://www.e90post.com/forums/showt...php?p=27457341
https://www.e90post.com/forums/showt...3#post27429233

[autoart]

You might have answered your own question. If the front 02 sensors are bad and causing a bank to run to rich it could fowl the spark plugs causing a misfire.

[Bimmer_Bro]

You log is weird for sure. There are times you are 10 psi below target but your wgdc is low.
Technically your wgdc should be high as they try to make target.
I am not familiar with your other threads but have you done a walnut blast? O2 sensors?
How old are the boost solenoids?
If you're getting a 30ff you need to look for vacuum and boost leaks. shot waste gates can cause this. #1 reason why N54 users have to upgrade or replace the turbos.

[kevinb21]

Originally Posted by autoart

You might have answered your own question. If the front 02 sensors are bad and causing a bank to run to rich it could fowl the spark plugs causing a misfire.

this makes sense, but if my bank 2 sensor 1 o2 sensor was shot why am I getting a 2,4,6, missfire under heavy load. Also I noticed the car takes sooooo long to spool up and go. When I hit it i hear spoooooolll thennn the power comes on.

[kevinb21]

Originally Posted by Bimmer_Bro

You log is weird for sure. There are times you are 10 psi below target but your wgdc is low.
Technically your wgdc should be high as they try to make target.
I am not familiar with your other threads but have you done a walnut blast? O2 sensors?
How old are the boost solenoids?
If you're getting a 30ff you need to look for vacuum and boost leaks. shot waste gates can cause this. #1 reason why N54 users have to upgrade or replace the turbos.

My car has had its valves cleaned when I swapped the engine, o2 sensors are unknown, I think one has been replaced no idea which one before I bought the car. Tomorrow I am going to attempt to adjust the wastegates to help it build boost but I am confused, why aren't my wgdc at 100%?

[Saif2018]

Originally Posted by kevinb21

This car is really just making me question my sanity here, 2010 BMW 335i coupe n54, spun a rod bearing so I put in a new n54 with upgraded rod bearings and it had a whole bunch of misfires and nonsense. Changed the plugs with colder ones, changed all 6 coils with Delphi, changed all 6 injectors with index 12 and most recently I bought a Brand new oem bmw HPFP and low pressure fuel sensor. The car KEEPS MISSFIRING. It is full bolt on MHD stage 2+ with chargepipe, downpipes, tial bov, and a FMIC. im running v9.0 mhd stage 2+ and every single time I go hard on the gas the car goes hard but not nearly as fast as my friends tuned n55 335i. The codes I am getting this time are
Cylinder 2 misfire
cylinder 4 misfire
cylinder 6 misfire
2C32 Lambda Control 2

This morning it also threw a 30ff.

Here is my log from this morning after changing the HPFP
https://datazap.me/u/kevinb21/may-29?log=0&data=21-26

its clear I am missing boost and my wastegate rattle is god awful so I know I need to adjust them and do the "temp fix"

other than that What seems to be the issue? btw, im aware the car has downpipes but it still has secondary cats but it smells baddddd, kinda like a toyota i had with a bad o2 sensor. And it gets 9mpg. BAD.

Previous thread(s)
https://www.e90post.com/forums/showt...6#post27577456
https://www.e90post.com/forums/showt...php?p=27457341
https://www.e90post.com/forums/showt...3#post27429233

Sounds like you might need both O2 sensors checked or replaced.

Can see several timing corrections as well, 5k onwards, this might be caused by the O2 sensor issue as posted earlier. Also which plugs and gap are you running with the colder plugs?

Have you pulled the plugs and checked them visually?
Although it's probably unlikely you could try swapping plugs/coils to rule them out. (assuming the misfires don't follow)

Something is definitely not right with your wastegates, if they rattling bad, then they probably shot. Wastegates need to close and stay closed to build boost. Otherwise you end up with severe lag and drivability issues.

[Saif2018]

Originally Posted by kevinb21

My car has had its valves cleaned when I swapped the engine, o2 sensors are unknown, I think one has been replaced no idea which one before I bought the car. Tomorrow I am going to attempt to adjust the wastegates to help it build boost but I am confused, why aren't my wgdc at 100%?

Your WGDC is not supposed to be at 100%, it should briefly spike up to near 100% then drop to to around 55% (depending on your tune/stage etc)

If it's constantly high, then it indicates a boost leak or wastegates probably shot

Wastegate fluctuations look like serious rattling going on,

[Dave92N54]

On mobile (as usual lol) so datazap looks like shit but what I could see is you are running really rich. Your AFR drops below 11 (typically want to see low 12, high 11s at the end of a pull) at the end of the last gear in that log (3rd). Then continue to watch your AFRs after the shift, bank 2 fluctuates. I had this happen for me, and it was a fried 02 (despite being less than 2k miles old, worked perfectly for like 2 weeks), but could also indicate a leaky injector.

You also have a ton of post shift timing corrections, literally every cylinder but 6. I know some are pretty normal, but I consistently get none in my logs. I see you did step colder plugs, what part number and what gap?

Oh I see you're running 91oct. Is there anywhere you can at least get 93? It won't solve your issues but will at least (hopefully) clean up the timing corrections. Fuel makes a very big difference on these cars, the difference in speed between a 1+ 91oct and a 1+ 93oct is quite noticeable.

[kevinb21]

Originally Posted by Saif2018

Sounds like you might need both O2 sensors checked or replaced.

Can see several timing corrections as well, 5k onwards, this might be caused by the O2 sensor issue as posted earlier. Also which plugs and gap are you running with the colder plugs?

Have you pulled the plugs and checked them visually?
Although it's probably unlikely you could try swapping plugs/coils to rule them out. (assuming the misfires don't follow)

Something is definitely not right with your wastegates, if they rattling bad, then they probably shot. Wastegates need to close and stay closed to build boost. Otherwise you end up with severe lag and drivability issues.

Originally Posted by Dave92N54

On mobile (as usual lol) so datazap looks like shit but what I could see is you are running really rich. Your AFR drops below 11 (typically want to see low 12, high 11s at the end of a pull) at the end of the last gear in that log (3rd). Then continue to watch your AFRs after the shift, bank 2 fluctuates. I had this happen for me, and it was a fried 02 (despite being less than 2k miles old, worked perfectly for like 2 weeks), but could also indicate a leaky injector.

You also have a ton of post shift timing corrections, literally every cylinder but 6. I know some are pretty normal, but I consistently get none in my logs. I see you did step colder plugs, what part number and what gap?

Oh I see you're running 91oct. Is there anywhere you can at least get 93? It won't solve your issues but will at least (hopefully) clean up the timing corrections. Fuel makes a very big difference on these cars, the difference in speed between a 1+ 91oct and a 1+ 93oct is quite noticeable.

The Car is running ngk 95770. they have not been gapped and are running whatever gap the factory gave them. The car is running 91 octane fuel because that is all I can get my hands on in Orange county CA other than e85, but I'm not sure if running an e30 tune is a good idea with my engine already being unhappy. I don't think I have a leaky injector, brand new index 12 from bmw coded and everything. My primary assumption based on my trash fuel economy and bad smelling exhuast is a ruined bank 2 sensor 1 sensor. If that one is fried id assume bank 1 isnt long for this world either. Aside from that My wastegate rattle is beyond terrible so I am going to adjust them until I can get new turbos. Other than that is there anything I can look into to fix the car?

[Dave92N54]

Dude, start by pulling your plugs and changing the gap ASAP. You didn't gap them? Why would you not do that?? I won't be surprised if that helps a lot of the issue. Their factory gap is .031 which is way, way too big. You need likely .022", I have mine at .020" but will be switching to .022" when it stops raining.

[Bimmer_Bro]

This is why I love the oem plugs.
No need to gap, rated for 475 ish hp.
Always used the Bosch 3 prong on stage 2+ without issue.

[Saif2018]

Originally Posted by Bimmer_Bro

This is why I love the oem plugs.
No need to gap, rated for 475 ish hp.
Always used the Bosch 3 prong on stage 2+ without issue.

Same here, until you need colder plugs no point going 1 step or 2 step.

[Dave92N54]

Well, I take back my .022" recommendation. May work for you but it's been misfire city for me. Drives fine, second I get into boost it just misfires.

[BSM n54iS]

Originally Posted by Dave92N54

Well, I take back my .022" recommendation. May work for you but it's been misfire city for me. Drives fine, second I get into boost it just misfires.

You said above you were at .020"?

But ya OP I agree, I'd kinda have gone the stock route with a new engine and upgrade after I know everything was proper.. But that gap is not correct at all. Then how many miles on those O2 sensors? You may as well replace them imo

[Dave92N54]

Originally Posted by BdSM n54iS

You said above you were at .020"?

But ya OP I agree, I'd kinda have gone the stock route with a new engine and upgrade after I know everything was proper.. But that gap is not correct at all. Then how many miles on those O2 sensors? You may as well replace them imo

Yes, I said I had .020" and would be switching to .022", I was curious if it would help my random, odd STFT spikes (honestly it looks like it may have but I did boost solenoids today too and I think that's more likely). Set .022", my stupid ass didn't drive it after, went to meet a friend and on the way once warmed up I stepped on it, misfire lol

[kevinb21]

Originally Posted by Dave92N54

Yes, I said I had .020" and would be switching to .022", I was curious if it would help my random, odd STFT spikes (honestly it looks like it may have but I did boost solenoids today too and I think that's more likely). Set .022", my stupid ass didn't drive it after, went to meet a friend and on the way once warmed up I stepped on it, misfire lol

damn. I had no idea going from .020 to .022 would trigger all those misfires, these engines really are picky persnickety machines. I can imagine with my random factory gap it would cause all these misfires, I will gap mine down to .020 and if that doesn't fix it I will go back to bmw factory plugs instead of the ngk 1 step colder iridium plugs. I think my boost solenoids might be broken considering I am not hitting 100% wastegate, but right now the car wastegates rattles so bad I need to get that dealt with before I touch anything else. The o2 sensor has been replaced but its unknown when and it makes sense that the car would need new o2 sensors with its rich smell and 9.0mpg, I will buy both bank 1 sensors. I am hoping that my n54 ends up making more power than the n55 because its cost me way more than an n55

[Dave92N54]

Well I want to update, I don't think gap made that difference. Two plugs actually kicked the dirt, even though I had no misfire issues before changing the gap to .022". Two new plugs, all at .022" car pulls crazy. First real pull since new boost solenoids, hit 16psi for the first time

[Ten-Zing]

When you swapped engines, did you swap any other supporting systems? Mosfet?

I kind of agree that going back to stock style plugs may help, and a bad O2 forcing full rich may foul a plug (especially plugs sensitive to 0.002" gap differences).

But honestly, you could potentially avoid all this with an ignition upgrade, not sure on the spark energy of the Delphi coils vs. Eldors? Probably not much if any at all.

I went through this somewhat with my car, kept going up on MHD tunes until I was ready for full E85 custom tune and my ignition was terrible. Upgraded that and it's like a whole new car. Made me question how viable the stock ignition is in these cars when even going MHD map 1.

I'm sure others will interject or state tons of people running stock ignition up to 500hp, etc. But this reminds me of the days when I ran old school hot rods on stock ignition distributor caps and then got an MSD 80 or 6AL (whatever) and the engine was like a whole new thing. Eventually even the mildest small block V8 would be running an MSD ignition cause everyone realized even on stock power the stock ignition was pretty weak.

I think that ignition isn't done because people can't or don't tie 'HP' improvements to the modification. But I'm willing to bet my car bone stock would have been improved with an upgraded ignition.

Just my .02 cents, but we're dicking around on 11 year old cars with stock 300hp and we want them to make 450hp on stock ignition and to be honest, I don't the stock ignition is even that great for stock power.

[BSM n54iS]

Originally Posted by Dave92N54

Yes, I said I had .020" and would be switching to .022", I was curious if it would help my random, odd STFT spikes (honestly it looks like it may have but I did boost solenoids today too and I think that's more likely). Set .022", my stupid ass didn't drive it after, went to meet a friend and on the way once warmed up I stepped on it, misfire lol

Ah that makes sense, are you running e or anything?

[Dave92N54]

Originally Posted by BdSM n54iS

Ah that makes sense, are you running e or anything?

Nope, though now that it's warmer... and a station about 15 minutes from me now has E... just need a tester kit all seems to be well now though. I'm curious if those plugs were somehow bad? I can't recall exactly when the STFT spikes started but I wanna say around the time I installed new plugs : Whatever though, I think that's enough on the subject. Don't wanna hijack OP's thread.

[kevinb21]

Originally Posted by Dave92N54

Well I want to update, I don't think gap made that difference. Two plugs actually kicked the dirt, even though I had no misfire issues before changing the gap to .022". Two new plugs, all at .022" car pulls crazy. First real pull since new boost solenoids, hit 16psi for the first time

Originally Posted by Ten-Zing

When you swapped engines, did you swap any other supporting systems? Mosfet?

I kind of agree that going back to stock style plugs may help, and a bad O2 forcing full rich may foul a plug (especially plugs sensitive to 0.002" gap differences).

But honestly, you could potentially avoid all this with an ignition upgrade, not sure on the spark energy of the Delphi coils vs. Eldors? Probably not much if any at all.

I went through this somewhat with my car, kept going up on MHD tunes until I was ready for full E85 custom tune and my ignition was terrible. Upgraded that and it's like a whole new car. Made me question how viable the stock ignition is in these cars when even going MHD map 1.

I'm sure others will interject or state tons of people running stock ignition up to 500hp, etc. But this reminds me of the days when I ran old school hot rods on stock ignition distributor caps and then got an MSD 80 or 6AL (whatever) and the engine was like a whole new thing. Eventually even the mildest small block V8 would be running an MSD ignition cause everyone realized even on stock power the stock ignition was pretty weak.

I think that ignition isn't done because people can't or don't tie 'HP' improvements to the modification. But I'm willing to bet my car bone stock would have been improved with an upgraded ignition.

Just my .02 cents, but we're dicking around on 11 year old cars with stock 300hp and we want them to make 450hp on stock ignition and to be honest, I don't the stock ignition is even that great for stock power.

Originally Posted by Dave92N54

Nope, though now that it's warmer... and a station about 15 minutes from me now has E... just need a tester kit all seems to be well now though. I'm curious if those plugs were somehow bad? I can't recall exactly when the STFT spikes started but I wanna say around the time I installed new plugs : Whatever though, I think that's enough on the subject. Don't wanna hijack OP's thread.

It seems to be clear that running .020-.022 is the desired range on my car and the route I will take. It is becoming more and more clear that my plugs and engine are not happy as even under a cold start I am noticing a big missfire and stumble on cold starts. Ive visually gone through everything And i can not find a vaccum leak or weak point for boost leaks so I assume its my wastegates not acting like functional wastegates just ordered new o2 sensors as well.

I don't think these engines should have ignition issues stock (with reasonable power demands) considering the s55 and the n26 run higher boost and use basically the same type of ignition. My car is a 2010 meaning it has the msd81 so I do not have any mofsets replaced. If i run e85 with upgraded turbos later I will buy the precision raceworks coils but for now I know numerous people making great power with the delphi coils. I actually went for a ride with my friend in his 07 e92 335i 6mt w mhd stage 2+ has more miles yet feels stupid fast.

As for plugs being fouled, it can very well be that you scraped the iridium coating off them. i don't know where I heard it... (scotty kilmer youtube channel?) But ive heard that on iridium plugs sometimes changing the gap in a certain way damages the tiny iridium coating which thus would ruin the plug. could be that or the rich mixture fouling it.

[Saif2018]

Originally Posted by kevinb21

It seems to be clear that running .020-.022 is the desired range on my car and the route I will take. It is becoming more and more clear that my plugs and engine are not happy as even under a cold start I am noticing a big missfire and stumble on cold starts. Ive visually gone through everything And i can not find a vaccum leak or weak point for boost leaks so I assume its my wastegates not acting like functional wastegates just ordered new o2 sensors as well.

I don't think these engines should have ignition issues stock (with reasonable power demands) considering the s55 and the n26 run higher boost and use basically the same type of ignition. My car is a 2010 meaning it has the msd81 so I do not have any mofsets replaced. If i run e85 with upgraded turbos later I will buy the precision raceworks coils but for now I know numerous people making great power with the delphi coils. I actually went for a ride with my friend in his 07 e92 335i 6mt w mhd stage 2+ has more miles yet feels stupid fast.

As for plugs being fouled, it can very well be that you scraped the iridium coating off them. i don't know where I heard it... (scotty kilmer youtube channel?) But ive heard that on iridium plugs sometimes changing the gap in a certain way damages the tiny iridium coating which thus would ruin the plug. could be that or the rich mixture fouling it.

Scotty Kilmer would have us peddling like Fred Flinstone if he could, lol.

Wouldn't pay attention to what that guy says,