misfire issues after tune

[beattiecj]

Just flashed my x35i with the bootmod3 91 octane stage 1 tune, took it for a quick test drive and ended up getting a drive train malfunction error with bunch of misfire codes. Just replaced plugs assume it could be a coil issue? All coils are secure. Flashed back to stock also same issue. Any thoughts?

Fixed see posts below was a bad spark plug that was brand new.

[Djhumvee]

Can you swap cylinder 4's coil with another cylinder and see if it still says cylinder 4 or if it detects a misfire on the cylinder you swap with?

[beattiecj]

Originally Posted by Djhumvee

Can you swap cylinder 4's coil with another cylinder and see if it still says cylinder 4 or if it detects a misfire on the cylinder you swap with?

Replaced all coils today, same issue. I’m guessing either a fuel injector or worse maybe. Saw on other forums the injector can go bad. Also getting a new set of codes.

Car has been reflated to stock and cleared codes before trying again.

[shimmy23]

ive been reading more and more on injector issues on both 50i and 35i. is this really that common? i've owned several BMW and cars and none have ever had injector issues.

[beattiecj]

I solved it, sometimes it’s so simple it’s hard. Brand new plug in cylinder 4 was causing the issue. Pulled it put it into cyclinder one got the same misfire codes. Swapped it and all is good, just coincidentally happened when I did the bm3 tune. 😂 cheers!