[aythatblackguy]

So my 2011 550i has has started to misfire under acceleration. If i drive like a grandma everything is fine but when i down shift to pass someone i get a drivetrain malfunction. Now the bmw dealer i got the car from replaced all 8 injectors and all plugs and coils before i bought it 400 miles ago so what gives.

[Bbmw535]

Originally Posted by aythatblackguy

So my 2011 550i has has started to misfire under acceleration. If i drive like a grandma everything is fine but when i down shift to pass someone i get a drivetrain malfunction. Now the bmw dealer i got the car from replaced all 8 injectors and all plugs and coils before i bought it 400 miles ago so what gives.

Sounds like plugs maybe coils. Not sure why they replaced everything. I had a missfire issues twice and one time happene to be plugs, second time one of the coils was bad.

[aythatblackguy]

Oh I forgot to mention it's only cylinder 1-4 that are misfireing

[Bbmw535]

Originally Posted by aythatblackguy

Oh I forgot to mention it's only cylinder 1-4 that are misfireing

Sounds like bad plugs or coils. I would take it back in and have it inspected before something else goes wrong

[Ironman273]

That happened to me. I had to replace the exhaust VANOS solenoid for that bank and it fixed it.

[EL Jeffe 5]

I had same issue only misfire on CY 8 like you said if I drive slow its fine as soon as I step on it over 2 RPM its throws out drive train malfunction.
Frist two times I took it to dealer they told me they couldn't replicate issue.
just other day I was coming back from store I step on it and there it goes Drive Train Malfunction. I was furious took it in show the manager as car was shaking like Hell
I told them to keep car for month if they have to @ that point I dint give a S#it.
Next day they called me SA told me they replaced coil 8 and spark plug its been good.
I hope it doesn't come back.
Good luck

[ezaircon4jc]

Originally Posted by Bbmw535

Sounds like plugs maybe coils. Not sure why they replaced everything. I had a missfire issues twice and one time happene to be plugs, second time one of the coils was bad.

A bad coil will take out a good coil and a bad coil will take out a good plug. They "should" normally be replaced together if one has failed.

[aythatblackguy]

Im going to rule out plugs and coils because they are all new.

[Ironman273]

https://bmwtechnician.com/2016/05/12...os-solenoid-2/

[SLVSRFR]

It could be anything from MAF, plugs, coils, or injectors. You need to get the codes read with BMW capable software, otherwise it's a crap shoot on the diagnosis.

[EL Jeffe 5]

Originally Posted by aythatblackguy

Im going to rule out plugs and coils because they are all new.

be careful even if you install new plugs and coils you still can have defected coil or plug.

[mpbmw94]

HPFP, should be replaced, I had the same issue after replacing coils, plugs and injectors. So far so good, hope this helps.

[Bmw doubles]

Codes are the first step to healing. You can't replace random parts and hope all goes well.