Q: Why does my E46 BMW M54 not start properly?

asked by on October 26, 2016

My BMW e46 always jumps on cold starts for a minute then clears changed coil pack and plugs and vacuum pipe to mass always code say cylinder 4 misfire could it be the injector

My car has 94000 miles.
My car has a manual transmission.

Ignition Coil Replacement $116.03 - $516.36 Get a Quote
Spark Plugs Replacement $96.63 - $636.71 Get a Quote
Fuel Injector Replacement $379.42 - $3631.88 Get a Quote
Fuel Pump Replacement $120.92 - $1186.72 Get a Quote
Engine is misfiring Inspection $79.99 - $89.99 Get a Quote

Hello there, many faults will cause your 2003 BMW 320i to run poorly on cold start and have a cylinder 4 misfire. You have done great in replacing the coil packs, plugs, and vacuum pipe. Common faults would be a fuel injector, fuel pump, vacuum leak, wiring harness fault, or a ECU fault. A qualified technician, such as one from YourMechanic, will be able to diagnose your cylinder 4 misfire and perform any repairs required to resolve the issue.

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