29D2high severityPowertrain
Misfire Cylinder 7
on 2012 BMW 740i 3.0L I6 Turbo N55 · RWD
What this code means
The engine control module detected a misfire on cylinder 7, meaning combustion is not completing correctly. This is the BMW equivalent of OBD code P0307.
Symptoms
- Rough idle
- Engine hesitation
- Check engine light flashing
Common causes
- Faulty ignition coil
- Worn spark plug
- Fuel injector fault
- Low compression or vacuum leak
Diagnostic steps
- Read freeze frame and confirm cylinder 7 misfire
- Swap coil and plug to another cylinder
- Test injector operation on cylinder 7
- Perform compression test on cylinder 7
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Other Powertrain codes on this vehicle
29CC
Misfire Cylinder 1
29CD
Misfire Cylinder 2
29CE
Misfire Cylinder 3
29CF
Misfire Cylinder 4
29D0
Misfire Cylinder 5
29D1
Misfire Cylinder 6
29E0
Lambda Additive/Idle Adaptation Limit, Bank 1
29E1
Lambda Additive/Idle Adaptation Limit, Bank 2
29E2
Lambda Multiplicative Part-Load Adaptation Limit, Bank 1
29E3
Lambda Multiplicative Part-Load Adaptation Limit, Bank 2