Faulty ignition coil on cylinder 9; Worn or fouled spark plug on cylinder 9; Leaking or clogged fuel injector on cylinder 9; Vacuum leak at the intake manifold runner for cylinder 9; Low compression due to worn piston rings or valve issues on cylinder 9; Damaged wiring or connector to the cylinder 9 coil or injector; Carbon buildup on intake valves causing poor airflow at start-up

DTC codes / BMW codes / P1358

P1358 · BMWMisfire During Start Cylinder 9

Q: What does code P1358 mean?

Misfire During Start Cylinder 9. P1358 on BMW vehicles indicates that the engine control module has detected a misfire specifically during the start-up phase on cylinder 9, which is typically found on V12 engines such as the M73 or N73. The computer monitors crankshaft speed fluctuations during cranking and identifies that cylinder 9 is not contributing power evenly, often before the engine is fully running.

P1358 on BMW vehicles indicates that the engine control module has detected a misfire specifically during the start-up phase on cylinder 9, which is typically found on V12 engines such as the M73 or N73. The computer monitors crankshaft speed fluctuations during cranking and identifies that cylinder 9 is not contributing power evenly, often before the engine is fully running.

SystemPowertrain

Code typeBMW specific

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Symptoms you may notice

Rough idle or shaking immediately after starting, especially when cold
Extended cranking time before the engine fires
Illuminated check engine light, sometimes flashing if the misfire is severe
Noticeable vibration or stumble during the first few seconds of running
Often no symptoms besides the warning light, particularly if the misfire is intermittent

Common causes, most likely first

Faulty ignition coil on cylinder 9
Worn or fouled spark plug on cylinder 9
Leaking or clogged fuel injector on cylinder 9
Vacuum leak at the intake manifold runner for cylinder 9
Low compression due to worn piston rings or valve issues on cylinder 9
Damaged wiring or connector to the cylinder 9 coil or injector
Carbon buildup on intake valves causing poor airflow at start-up

How to diagnose and fix it

Scan all modules for stored and pending fault codes, and record freeze-frame data to confirm the misfire occurs only during start-up
Perform a visual inspection of the cylinder 9 ignition coil, spark plug, and injector connectors for damage or corrosion
Swap the ignition coil and spark plug from cylinder 9 with a known-good cylinder and recheck for misfire migration
Conduct a compression test and cylinder leak-down test on cylinder 9 to rule out mechanical faults
Test the fuel injector for cylinder 9 with a noid light or injector balance test to verify pulse and flow
Smoke-test the intake system to check for vacuum leaks specific to cylinder 9
If all electrical and mechanical checks pass, reprogram or update the engine control module software as per BMW service bulletins

Start-up misfire on BMW V12 engines

A P1358 code often appears alongside P0300 or P0309, and technicians who replace all coils without swapping first frequently miss a simple spark plug fault.
The misfire may only occur during the first few seconds of cranking, so a standard running compression test can appear normal; a cranking compression test is essential.
BMW V12 engines are sensitive to battery voltage during cranking, and a weak battery can cause false start-up misfire codes on multiple cylinders including cylinder 9.
Carbon buildup on the back of intake valves is a common cause on direct-injection BMW engines, leading to start-up misfires that disappear once the engine warms up.
The engine control module may set P1358 even when the misfire is caused by a faulty crankshaft position sensor signal, so always check for related sensor codes before replacing ignition components.

Can I keep driving with P1358?

You can drive the vehicle short distances to a repair shop, but avoid hard acceleration and prolonged driving because a persistent start-up misfire can damage the catalytic converter and cause rough running. If the check engine light flashes, stop driving and seek immediate service.

Tools that help

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Guidance is general and written for BMW vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.