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Matt
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 22166
Experience:  BEng hons Mech engineering, in auto industry 22 years
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bmw 320 SE 2007 manual misfire with management light on,

Customer Question

bmw 320 SE 2007 manual
misfire with management light on, total loss of power to move the car. fault stated misfire at 3, also notice slight misfire before this fault at idle
Submitted: 3 years ago.
Category: BMW
Expert:  Matt replied 3 years ago.
Hello

On any car if you get a check engine light or other fault light this typically means one or more of the sensors has failed or has a faulty connection.

The fault can be something quite simple and nothing that’s going to stop the car to something quite major that will reduce engine power and possibly stop the engine

The ECU senses this and may put the car into 'limp home' mode which typically limits the revs and the amount of power available. Usually the car is safe to drive for a short distance as the mode is intended is intended to get you home without incurring any engine damage

The quickest route to repair is to have the car plugged into a diagnostic machine which will read off the fault code stored in the ECU (providing the light is still on at this point) and indicate which sensor has failed or whether the fault is more serious.

You can do a very rough and ready check yourself by unplugging sensors one at a time and seeing if any of them change the driving condition which would indicate the most recently unplugged sensor is the faulty one. This method is not foolproof though and reading a fault code off is the better method.

You can also try resetting the car by removing both battery leads and clamping them together for 10 mins as this will reset everything so if the light re-appears then the fault is still there.
Disconnect the battery cables and clamp them together for 10 mins. Remove both battery leads from the battery then use a nut and bolt or G-clamp to hold both battery lead terminals together.

This discharges any capacitors / memory within the ECU and around the car so ensures all memory settings are wiped clear - back to the factory default.

This will reset all the systems on the car and you may need the radio security code to get it going again, and ensure that the keys are in your hand when you re-connect the battery as the car may lock and turn on the alarm

from your description I suspect there's an issue with one of the major sensors on the engine
This could be a wiring issue as things tend to expand when hot and its possible a poor or partial electrical connection is being pushed apart on one of the major sensors so check the connection plug and wiring to the following;
Airflow meter
Crank position sensor
Cam position sensor
O2 sensor
Throttle position sensor
Expert:  Matt replied 3 years ago.
Hi do you still need help with this?