[marcel b]

so, I had all coils, injectors and plugs replaced last week after I had a misfire in Cyl6. 2 Days later same issue. BMW replaced the HPFP today and went on a testdrive and had again misfires! My service manager called me today that they have no clue what the problem is. HOW RIDICULOUS IS THAT

They will get a special software from BMW (WTF???) and hope that this will help. My car has the latest SW already, so I have no clue why my car would need special software . Not even sure I want to have a special software... next time there is a new software update I will probably screwed again.

I have no tune, just the original Power Kit with a bigger oilcooler and a ETS FMIC.

Any suggestions to put the guys in the right direction

[badass335]

Thats not looking good!! I seem to have misfires on high rpms but replacing everything still. I'll be following you on this!

[marconi118]

do you have misfires codes?

I am in the same situation with different car: 07/07 335i MSD80 no power kit

had misfires at WOT (codes in DME), dealer replaced 6 injectors

After injector replacement, misfire at idle and partial throttle but no DME code.

Dealer replaced 6 plugs + 6 coils, no change: warm engine idle is fluctuating, engine vibrates and you can feel the misfires on the seat.

Car examined by the inspector engineer from BMW belgium, conclusion: this is a normal idle for a lean burn N54 engine.
I keep repeating to the dealer that engine was running smooth when car was 1 year old, so why would it be vibrating now? It isn't normal.

I am in the same situation as you: they don't want to do anything

My hypothesis: there is fluctuation in the production chain of injectors.
Some of them (unlucky that we got at least one in our car) are giving less quantity of fuel compared to the calibration numbers printed on them.
So now the DME has the right calibration numbers but the injector is outputting less fuel than expected => misfire

BUT HOW TO PERSUADE THE DEALER OF THIS????

THEY STATE I AM CRAZY, NEW injectors can't be faulty, no change needed.

[marconi118]

no lemon trees in Europe

In the states my car would have been replaced under lemon one year ago already

[cstmx_ryder]

Did the dealership check the LPFP? Or the fuel sensor that's in the tank, or something like that.......I had that replaced by the dealership because they thought that might have caused my long cranks, but it turned out to be the HPFP.

So just have them check those just to be 100% sure......My .02

[badass335]

I get misfire codes but with tune only. I believe in your case, the performance upgrade may be enough to push it over as well. In my case, 95% of the time it's cyl 6. 4% of the time it's cyl 5 and maybe a cyl 2or 4 but rare.

[marcel b]

Originally Posted by cstmx_ryder

Did the dealership check the LPFP? Or the fuel sensor that's in the tank, or something like that.......I had that replaced by the dealership because they thought that might have caused my long cranks, but it turned out to be the HPFP.

So just have them check those just to be 100% sure......My .02

I will tell them this. I was hoping that with the change of the HPFP the problems finally would be over.

I only had codes thrown for Misfiring Cyl6, no other cylinders.

[marcel b]

Originally Posted by marconi118

no lemon trees in Europe

In the states my car would have been replaced under lemon one year ago already

In some EU countries they have to take back the car as well if they cannot solve the issue. I know Germany and also here in Switzerland this happens. Not that easy though. With the changes I did (suspension and Drexler LSD) I am also not really looking forward to change as this would cost me a great deal of money. They need to fix the issue, should be not too much to ask for.

[marcel b]

Originally Posted by marconi118

do you have misfires codes?

I am in the same situation with different car: 07/07 335i MSD80 no power kit

had misfires at WOT (codes in DME), dealer replaced 6 injectors

After injector replacement, misfire at idle and partial throttle but no DME code.

Dealer replaced 6 plugs + 6 coils, no change: warm engine idle is fluctuating, engine vibrates and you can feel the misfires on the seat.

Car examined by the inspector engineer from BMW belgium, conclusion: this is a normal idle for a lean burn N54 engine.
I keep repeating to the dealer that engine was running smooth when car was 1 year old, so why would it be vibrating now? It isn't normal.

I am in the same situation as you: they don't want to do anything

My hypothesis: there is fluctuation in the production chain of injectors.
Some of them (unlucky that we got at least one in our car) are giving less quantity of fuel compared to the calibration numbers printed on them.
So now the DME has the right calibration numbers but the injector is outputting less fuel than expected => misfire

BUT HOW TO PERSUADE THE DEALER OF THIS????

THEY STATE I AM CRAZY, NEW injectors can't be faulty, no change needed.

My dealer is doing a lot for me now and clearly states this is not normal. The acknowledge the issue, they just do not know how to fix it. Am sure they will go to the bottom of this to fix it.

[marcel b]

Originally Posted by badass335

I get misfire codes but with tune only. I believe in your case, the performance upgrade may be enough to push it over as well. In my case, 95% of the time it's cyl 6. 4% of the time it's cyl 5 and maybe a cyl 2or 4 but rare.

I cannot imagine the power kit / power increase is causing the issue. The misfiring I had last Friday (after coil, injector and plug change) happened with a warm engine, with not even 50 throttle in 4th gear driving at 2500 RPM. So not like going WOT.

[marconi118]

I don't want to change the car to get a N55!

I have got the same, light misfire at 50% throttle 2500rpm. Unfortunately for me it is so light that the DME don't record any fault code.
So I don't even know witch cylinder it is
I really suppose that the misfire is caused by lean A/F (engine goes lean burn mode at light throttle, only at WOT the power kit acts...)
Try to replace injector of cyl6 again!

[LJS330i]

I had the sames exact set of issues. My dealer ended up replacing the valve seals after 7 attempts. That seemed to do it. I was already deep into the trade assist process when they got it right.

LJS330i.

[rbaldwin28]

I have the same issue as badass335 and BMW is installing a new HPFP right now so we will see. This is not the first time I have had a new HPFP and last time there were no issues for about 4-5000 miles. 10705 10706 codes are always in my DME. This is a real problem and I have heard the spark plugs and coils and injectors stuff from so many people and that just isn't it. I will let you guys know about the pump. Fingers crossed.

[rbaldwin28]

Does every one with this issue have an auto transmission? Step or DCT?

[marcel b]

Originally Posted by rbaldwin28

Does every one with this issue have an auto transmission? Step or DCT?

I have a DCT....

[cstavaru]

I think the valve seats thing may be one possible answer if everything else was replaced...maybe carbon buildup ?

It scares me...I have the Power Kit as well and a failing HPFP four months before the warranty is over.

[rbaldwin28]

Originally Posted by marcel b

I have a DCT....

Badass335 and I both have Step and I have noticed that others with this problem have auto transmissions also. I only need to run 1 psi over stock and it will miss fire. How much boost does the power kit run? Stock is 8.9 psi and I believe you are always over that because of your power kit from BMW so you can't get back to 8.9 to see if it goes away. Most people I have come across just sell the tune and run stock to avoid the miss fires but that just isn't possible for you.

[joec500]

Originally Posted by badass335

I get misfire codes but with tune only. I believe in your case, the performance upgrade may be enough to push it over as well. In my case, 95% of the time it's cyl 6. 4% of the time it's cyl 5 and maybe a cyl 2or 4 but rare.

I am in the exact same boat, are you 2007 MSD80?

But I am 6MT

[a32guy]

Did they do a leakdown on the motor?

[marcel b]

Originally Posted by a32guy

Did they do a leakdown on the motor?

nope, not what I know. the replaced the hpfp and where surprised they issue was still there. this was today. I will call them tomorrow to check what they will do and to propose some points for them to check.

[marcel b]

Originally Posted by rbaldwin28

Badass335 and I both have Step and I have noticed that others with this problem have auto transmissions also. I only need to run 1 psi over stock and it will miss fire. How much boost does the power kit run? Stock is 8.9 psi and I believe you are always over that because of your power kit from BMW so you can't get back to 8.9 to see if it goes away. Most people I have come across just sell the tune and run stock to avoid the miss fires but that just isn't possible for you.

ok... never heard about this. interesting that I had the kit since 8 months and quite some miles with no issue. I am so happy to have the power kit and not an after market tune, so bmw has to take care and cannot blame it on a tune.

[maui86]

try seafoam or something that would show any possible exhaust leaks near the o2 sensors.

i have idle vibration and light throttle/boost misfires(but not enough to throw codes). i can see lean spiking happening. i replaced the o2's...didn't work...then i seafoamed and found an exhaust leak at the vband. under idle and light throttle i'm pretty sure air can get sucked in and fool the o2 sensors its running lean.

question though to the experts...if the ecu is being told its getting extreme lean conditions, does it automatically shoot more fuel to compensate? to me, this makes sense to do, but if the engine isn't really running lean and now the engine(or one bank) is too rich, could that cause misfires? it could explain the vibrations. i ask this because the bank(2) with the leak, the o2 sensors were covered in soot. yet bank1 wasn't.

i'm waiting for the vband clamp to arrive so i can replace all the gaskets and clamps to have no reason for a leak.

teri