[rif75]

Hi all,

I would like to share with you my issue and maybe get some help or idea. The car is BMW 335i F30 from 12/2012 with 110000km or 69000miles

Car was running perfect before the plugs replacement...

I had a bad suprise after replacing the spark plugs by aftermarket Bosch. I had a lot of misfire after the new plugs install. After looking on the different threads, I saw that aftermarket plugs are not good on this car so I went to buy OEM plugs and it was better but still missfire, 102002 Air mass, plausibility: Air mass too low and 118401 Mixture control: Mixture too learn, large deviation.

I have inspected my valve cover for leaks but nothing, I have still made a gasket replacement on it. Broke the vent hose in the process because plastic of the hose was too old. I have been waiting a new one from BMW for more than a month and they told me July today for delivery...I have tested the car with a vent hose from another 335i so not the issue here.

I have tested the car with another coils and still the same issue.

I have tested the compression in the 6 cylinders and they were all around 11.5-12 bars. That would be 174psi.

I have made 2 logs to have more input but I need an expert because I do not see anything special here.

Only thing that I can imagine is injector issue since the pressure in the rail is ok.


Please HELP Car is blocked for more than a month now...

[rif75]

Forgot to add the logs

[BMWILUVU]

What made you change the plugs in the first place? Did you try to put them back? If this is true it sounds like you caused an issue with this install.

[thejeremyman9]

Your procedure is strange...

You replaced spark plugs and got misfires, so then you decided to do a VCG that wasn't leaking? You now introduced a bunch of additional variables into the equation. It could have been any number of things you touched during that work, but start with what you touched during the initial plug install and go from there. Air mass too low might be a vacuum leak you introduced post MAF.

[rif75]

I did the spark plugs because it was as per maintenance schedule.

Valve cover, i did it because i did read somewhere that a leak on the valve cover could create missfire but was a bad idea. I have removed it 2 times because had a leak after the gasket replacement because it was pinched. Now all good and no leaks.

Anything visible on the logs guys?

[n55david]

Originally Posted by rif75

I did the spark plugs because it was as per maintenance schedule.

Valve cover, i did it because i did read somewhere that a leak on the valve cover could create missfire but was a bad idea. I have removed it 2 times because had a leak after the gasket replacement because it was pinched. Now all good and no leaks.

Anything visible on the logs guys?

maybe.. you have to actually post the logs lol

[thejeremyman9]

Originally Posted by rif75

Forgot to add the logs

Upload the csv to datazap and post the link(s)

[rif75]

It has been quite a long time ago since I was sharing my logs from my n54


https://datazap.me/u/rif75/bmw-335i-...og=0&data=3-13

https://datazap.me/u/rif75/bmw-335i-...og=1&data=3-13

[thejeremyman9]

Originally Posted by rif75

It has been quite a long time ago since I was sharing my logs from my n54


https://datazap.me/u/rif75/bmw-335i-...og=0&data=3-13

https://datazap.me/u/rif75/bmw-335i-...og=1&data=3-13

It's more or less impossible to discern anything from logs like this. You need WOT logs. https://f30.bimmerpost.com/forums/sh....php?t=1732327

[rif75]

I wanted to avoid pulling the car with that issue but if it is needed to have the issue identified, will do.

Thanks

[thejeremyman9]

Originally Posted by rif75

I wanted to avoid pulling the car with that issue but if it is needed to have the issue identified, will do.

Thanks

Then run other diagnostic procedures besides datalogs. Start checking all the things you touched when you did the recent maintenance.

[rif75]

Quick update guys.
After a feedback from another owner of 335i f30, he had several plugs from BMW that were not working so I went to BMW to have the ones placed on the cylinders that were giving me misfire replaced again by new plugs from BMW and car is now fixed.

I lost a lot of time assuming that the new plugs from BMW were 100% reliable. I Have changed the coils for nothing even if with that mileage, cannot hurt. I was very close to replace the injectors...

From what I see here, the Bosch plugs are not good, regardless of if taken from Bosch or from BMW and I had to buy 6 from Bosch and 9 from BMW to have the car working normally. I had this bad experience few year ago on my N54 for both, plugs and coils so in the future, I won t take this brand for those 2 parts...

Thanks for your advice

[F32Fleet]

Originally Posted by rif75

Quick update guys.
After a feedback from another owner of 335i f30, he had several plugs from BMW that were not working so I went to BMW to have the ones placed on the cylinders that were giving me misfire replaced again by new plugs from BMW and car is now fixed.

I lost a lot of time assuming that the new plugs from BMW were 100% reliable. I Have changed the coils for nothing even if with that mileage, cannot hurt. I was very close to replace the injectors...

From what I see here, the Bosch plugs are not good, regardless of if taken from Bosch or from BMW and I had to buy 6 from Bosch and 9 from BMW to have the car working normally. I had this bad experience few year ago on my N54 for both, plugs and coils so in the future, I won t take this brand for those 2 parts...

Thanks for your advice

Bosch aa a whole is fine. Bosch is the OE supplier for the N55.

[rif75]

I know that Bosch is a very good brand for a lot of things and I buy a lot of Bosch items but how can it be fine when after buying a total of 19 plus, half were defective, including the ones bought from BMW.
The one that I bought from BERU are all working. Had issues with Bosch plugs and coils for my N54 in the past. Never had any issues with BERU and NGK.

It is not isolated since another owner had the same issue when bought plugs from BMW last month like I said.