[dezy376]

Hi hope someone can help me on here, i have just bought a 2006 318i M-Sport , on start up either hot or cold the car runs rough and if i touch the accelerator the car will misfire on cyl 4 if i don't touch the accelerator the car will idle fine after 15 seconds and then can be driven absolutely fine with no issues at all the car had been to BMW and they said the car need a Valvetronic Stepper which i have replaced and relearned the setting i have also changed the following,

Coils
Spark plugs
Cam Shaft Sensor
removed cleaned and swapped on the vanos solenoids
Cam Shaft timing all checked & ok

hopefully someone will have idea what to do next.

[cranelec]

Not sure this is YOUR part # 11377524879 (realoem.com). An eccentric shaft sensor will cause a cold start rough idle without setting the SES light or throw codes.
Remove the female harness electrical connector and look for oil residue in the sensor. If oil is present, you have a bad sensor.

Mike

[dezy376]

Thanks mike i have also come to this conclusion and will be changing the sensor this weekend.

[dezy376]

Hope this helps other people, i changed the sensor this weekend and all problems fixed