[street 335i]

I have a 07 335i with basically everything done to prevent misfires but still I have a bad one. I have all index 12 injectors which have less than 2000 miles on them. Precision racework coils and coil pack, new.022 gapped 2step colder plugs, and new seals on the injectors. No matter what I do the car has a bad misfire in cylinder 1 even moving injectors and recoding them or moving coils has no effect. The car idles very rough and you can hear it popping at idle and breaking up under load. Mosfets have been done aswell and I don’t think I saw any blow by on the injector.
I checked the voltage when the car was on from the engine terminals and read 13.9-14.3 volts.
If anyone has any ideas on what I should triple check please let me know

[macanic21]

Did you move the plug?
Are you sure there isn't an issue with the connectors causing bad contact like if someone stuck a pin in them to test things and spread out the connector?

Compression test.
Leak down test.
If you have fuel and air, compression is the only thing left. Could be a valve/ valve train issue if its popping out the intake or exhaust like you say.

Is it a hard miss, like it never fires that cylinder at all?

Could also be a wiring issue with the injector or coil. Try listening to the injector with a screw driver to make sure it sounds the same as the others.

Next steps would be verifying signals with an oscilloscope if compression is good.

[street 335i]

Originally Posted by macanic21

Did you move the plug?
Are you sure there isn't an issue with the connectors causing bad contact like if someone stuck a pin in them to test things and spread out the connector?

Compression test.
Leak down test.
If you have fuel and air, compression is the only thing left. Could be a valve/ valve train issue if its popping out the intake or exhaust like you say.

Is it a hard miss, like it never fires that cylinder at all?

Could also be a wiring issue with the injector or coil. Try listening to the injector with a screw driver to make sure it sounds the same as the others.

Next steps would be verifying signals with an oscilloscope if compression is good.

I have moved around the coils and tested different coil packs on cyl 1 and the misfire stays on cyl 1. Today I noticed the voltage through mhd when I scan the car is around 13.2 when running. But when tested on the jump points and on the alternator it’s more like 14.2. Could it possibly be an alternator issue or some parasitic loss I need to track down

I will attach the codes I got from the car this morning. I will also check the injector seals on cyl 1 for a loose fit or anything else. Will most likely swap cyl 1 and 2 injectors.

Photos taken at idle after 20 minutes of driving.

[macanic21]

So you never moved the spark plug?

[street 335i]

Originally Posted by macanic21

So you never moved the spark plug?

They are brand new spark plugs gapped to .022

[street 335i]

Here is a log of the cyl1 *crk. It is moving constantly and the other cylinders stay at a flat 0. How do I test for if my spark plugs are not getting enough power?
https://datazap.me/u/street335i/cyl-...og=0&data=3-21

[macanic21]

Originally Posted by street 335i

They are brand new spark plugs gapped to .022

Do you know what new stands for? Never Ever Worked. I was just through this, try moving the plug, its free and easy.