Monday, February 18, 2008

BMW Service.


Wouldn't it be good to know all your servicing costs in advance? Well, that's exactly what BMW Service Inclusive provides. Once you have decided which particular option best suits your needs - there are four options available, you can then simply relax, and look forward to enjoying care-free driving, courtesy of BMW Service Inclusive.
There is a BMW Service Inclusive option to suit everyone. You can choose from either a 3 year/36,000 miles or 5 year/60,000 miles duration, as well as opt to include maintenance cover if you wish.

You have the option to have the work carried out at any one of over 150 BMW Authorised Workshops Nationwide. All work is carried out by fully qualified BMW Approved Technicians using Genuine BMW parts with a 2-year unlimited warranty. BMW Service Inclusive maintains manufacturer service history, which can enhance the resale value of your car. BMW Service Inclusive is also fully transferable to subsequent owners. All this in a one-off, inflation-proof advanced payment.

Value added investment

The BMW Service Inclusive options are only offered with new BMWs. BMW Service Inclusive options remain available for up to 60 days after first registration. Should you sell your BMW before expiry of the chosen duration, or prior to the advised mileage limit, any remaining benefits are fully transferable to subsequent owners.

from here

Fuel system

Fuel system

On carburettor models, the fuel pump supplies fuel under pressure to the carburettor. A needle valve in the float chamber maintains the fuel at a constant level. A fuel return system channels excess fuel back to the fuel tank. On fuel injection models, an electric fuel pump supplies fuel under constant pressure to the fuel rail, which distributes fuel to the injectors. The electric fuel pump is located inside the fuel tank on later models, or beside the fuel tank on early models. Early models also have a transfer pump located in the fuel tank. The transfer pump acts as an aid to the larger main pump for delivering the necessary pressure. A fuel pressure regulator controls the pressure in the fuel system. The fuel system also has a fuel pulsation damper located near the fuel filter. The damper reduces the pressure pulsations caused by fuel pump operation, and the opening and closing of the injectors. The amount of fuel injected into the intake ports is precisely controlled by an  lectronic Control Unit (ECU or computer). Some later 5-Series models have a fuel cooler in the return line.

Electronic control system (fuel injection system)

Besides altering the injector opening duration as described above, the electronic control unit performs a number of other tasks related to fuel and emissions control. It accomplishes these tasks by using data relayed to it by a wide array of information sensors located throughout the engine compartment, comparing this information to its stored map, and altering engine operation by controlling a number of different actuators. Since special equipment is required, most fault diagnosis and repair of the electronic control system is beyond the scope of the home mechanic. Additional information and testing procedures for the  missions system components (oxygen sensor, coolant temperature sensor, EVAP system, etc.)

 from here

Anti-theft audio system

car audio installation sample

General information

Some models are equipped with an audio system having an anti-theft feature that will render the stereo inoperative if stolen. If the power source to the stereo is cut, the stereo won’t work even if the power source is immediately re-connected. If your vehicle is equipped with this anti-theft system, do not disconnect the battery or remove the stereo unless you have the individual code number for the stereo. Refer to the owner’s handbook supplied with the vehicle for more complete information on this audio system and its antitheft feature.

Unlocking procedure

1 Turn on the radio. The word “CODE” should appear on the display.

2 Using the station preset selector buttons, enter the five-digit code. If you make a mistake when entering the code, continue the five-digit sequence anyway. If you hear a “beep,” however, stop immediately and start the sequence over again. Note: You have three attempts to enter the correct code. If the correct code isn’t entered in three tries, you’ll have to wait one hour, with the radio on, before you enter the codes again.

5 Once the code has been entered correctly, the word “CODE” should disappear from the display, and the  radio should play (you’ll have to tune-in and enter your preset stations, however).

6 If you have lost your code number, contact a BMW dealer service department.

from here

Sunday, February 17, 2008

Ignition sensors (Motronic system) - check and renewal

Note: Some models are equipped with a TDC sensor mounted on the front of the engine. This sensor is strictly for the BMW service test

unit, and is not part of the Motronic ignition system.

Speed and position sensors


1 Locate the two electrical connectors for the sensors (see illustrations). The grey connector is for the position sensor, and the white connector is for the speed sensor.

2 Using an ohmmeter, check the resistance between terminal 1 (yellow wire) and terminal 2 (black wire) on the sensor side of each connector. The resistance should be 860 to 1,060 ohms.

3 Also check the resistance between terminal 3 and either terminal 1 or terminal 2. The resistance should be approximately 100 000


4 If the reading(s) are incorrect, renew the sensor(s).


5 Remove the sensor mounting screw(s), using an Allen key where necessary, and pull the sensor(s) from the sockets. Disconnect

the wiring from one sensor at a time - be sure the connectors are not interchanged when fitting new sensors. The bellhousing is marked

with a B for the position sensor (grey connector) and D for the speed sensor (black connector) (see illustration). Note: It is a good idea to check the condition of the raised pin on the flywheel while the sensors are out of the sockets. Turn the engine by hand as necessary to bring the pin into view.

6 Tighten the sensor mounting screw(s) securely, but be careful not to overtighten.

 Pulse sensor (later models)


7 Locate the two electrical connectors for the sensor (see illustrations). Disconnect the electrical connector from the front.

8 Using an ohmmeter, check resistance between terminal 1 (yellow wire) and terminal 2 (black wire) on the sensor side of each connector (see illustration). The resistance should be 500 to 600 ohms.

9 If the reading is incorrect, renew the sensor.


10 Remove the pulse sensor mounting bolt using a 5 mm hex spanner (see illustration). Withdraw the sensor from its bracket and

remove it.  

11 When fitting the new sensor, use a brass feeler gauge to position the tip of the sensor the correct distance from the pulse wheel (see illustration). 

12 Tighten the mounting bolt, but be careful not to overtighten it

Ignition system - general information and precautions

The ignition system includes the ignition switch, the battery, the distributor, the primary (low-voltage/low-tension or LT) and secondary (high-voltage/high-tension or HT) wiring circuits, the spark plugs and the spark plug leads. Models fitted with a carburettor or L-Jetronic fuel injection are equipped with a Transistorised Coil Ignition (TCI) system. Models fitted with the Motronic fuel injection system have the ignition system incorporated within the Motronic system (Digital Motor Electronics or DME). is running, the ignition timing is continually

changing, based on the various input signals to the ECU. Engine speed is signalled by a speed sensor. Early Motronic systems have

the position reference sensor and the speed sensor mounted on the bellhousing over the flywheel on the left-hand side. Later Motronic

systems have a single sensor (pulse sensor) mounted over the crankshaft pulley. This sensor functions as a speed sensor as well as

a position reference sensor. Refer to Section 12 for checking and renewing the ignition sensors. Note: Some models are equipped

with a TDC sensor mounted on the front of the engine. This sensor is strictly for the BMW service test unit, and it is not part of the

Motronic ignition system

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