2014 BMW 535i xDrive Misfires

louisdi
Sun, 29 Oct 2023 15:32:27 +0000
Maintenance/Repairs

1: Plugs replaced car appears to be running great. Drive it around for a day without issue.
2: Brake pads need replacing so replace brake pads
3: Test drive after pad replacement, no issues
4: Come back an hour later, drive car and immediately have misfires and issues, code reader has multiple codes, P0300, P0304, P0305 and P0456.
5: Move plugs to different cylinders and the misfires follow the plugs
6: Decide to replace all the plugs (again and go from Bosch to Champion), everything ran great. For a day. All of a sudden last night we are now getting a misfire on cylinder 6 again (P0306).
7: Moved swapped coil from Cylinder 6 to 1, misfire stays on cylinder 6 (P0306). Move plug to cylinder 1, misfire changes to cylinder 1 (P0301).
8: Replace plug in cylinder 1 (this is now the 3rd new plug) and it all runs great again.
9: Drive a few more times, and now we have a new misfire in cylinder 6 (P0306).

AHHHHH. Please help. We’re at wits end.

13 posts - 7 participants