BMW 3 Series E30 car fuel injection system

Injection unit L-/LE-/LU-JETRONIC, MOTRONIC
Depending on the model, variants of the fuel injection device based on the L-Jetronic device, such as Lfc-Jetronic, are installed on BMW injection engines....

L-/LE-JETRONIC injection device
The L-/LE-Jetronic injection unit is an electronic injection unit in a gasoline engine that delivers pulsed fuel into the intake pipe in front of the intake...

LU-JETRONIC injection device
Lambda probe (oxygen sensor) on cars with a regulated catalyst, it measures the oxygen content in the exhaust gases and transmits the information to the...

MOTRONIC injection device
The engine speed is measured directly by an inductive speed sensor located at the flywheel. Caution: When working on the fuel injection device, be extremely...

Rules for cleanliness when working on the fuel injection device
Thoroughly clean the joints and around them with petrol. Fold the removed parts on a clean film or paper and cover. Do not use rags with lint! Cover open parts...

Safety regulations for working on the fuel injection device
Do not start the engine with a loose battery. When the battery is discharged, do not start the engine with a quick battery charger. Never disconnect the...

Checking the idle speed and CO content
Attention: With Motronic installed, the idle speed is electronically controlled and cannot be adjusted. L-/LE-Jetronic Connect instruments for measuring the...

Removal and installation of the fuel pump
The fuel pump is located under the bottom of the vehicle near the fuel tank. Withdrawal Disconnect the ground wire from the battery. Unscrew the electrical...

Removal and installation, check of the starting valve
The start valve provides additional fuel to the intake manifold during a cold start. Valve failure makes it difficult to start the engine (both cold and hot)...

Removing and installing, checking the thermal time switch
The thermal time switch limits the injection time of the starting valve depending on the engine temperature. A defective thermal switch makes it difficult to...

Removal and installation, checking the temperature sensor
Motronic, L-/LE-/LU-Jetronic The temperature sensor measures the temperature of the engine and transmits this information to the control unit. The temperature...

Checking and replacing the additional air damper
As the engine warms up, it requires more air/fuel mixture than the throttle position dictates. To increase the mixture supply with the help of an additional...

Checking, adjusting and replacing throttle switches
Examination Disconnect the throttle switch connector. Connect an ohmmeter to the throttle switch contacts -2- and -18-. Set value: 0 ohm. Give throttle lever a...

Removal and installation of the control unit
The control unit is located behind the trim in the glove box. Withdrawal Disconnect the ground wire from the battery. Open the glove box and pull your fingers...

K-JETRONIC injection device
The K-Jetronic injection unit is installed on BMW-318i vehicles manufactured before September 1983. The K-Jetronic is a mechanical injection device for...

Checking the idle speed and CO content
Connect instruments for measuring the number of revolutions and the CO content in accordance with the instructions for their use. Warm up the engine to...

Maintenance work on the fuel injection device
Replacing the air filter element The filter element should be replaced every 20,000 km. If there is a lot of dust, replacement should be done more often....

Diagnosis of malfunctions of the injection system
Before troubleshooting using this diagnostic table, the following conditions must be met: eliminate driver errors when starting the engine. Both on a cold and...