Imprint Contact 868 Videos
900.000 Callings


Wheel change
Save Energy

Video Petrol Injection 1
Video Petrol Injection 2
Video Petrol Injection 3
Video Petrol Injection 4
Video Petrol Injection 5
Video B-Dir. Combustion
Video Dir. Petrol Injection 1
Video Dir. Petrol Injection 2
Video Dir. Petrol Injection 3
Video Dir. Petrol Injection 4
Video Dir. Petrol Injection 5
Video Petrol Injection Kugelf.
Video Homog. Working
Video Stratified-charge Oper.
Video Fuel Distrib.
Video Induction System
Video Petrol Injection Signal 1
Video Petrol Injection Signal 2
Video Idle Speed Device
Video Mass Air Flow Sensor 1
Video Mass Air Flow Sensor 2
Video Mass Air Flow Sensor 3
Video System Press. Reg. 1
Video System Press. Reg. 2
Video Injection Valve
Video Ind. Pulse Generator
Video Single Point Injection 1
Video Single Point Injection 2
Video Single Point Injection 3
Video Single Point Injection 4
Video Unregistrated Air
Video Lambda Sensor 1
Video Lambda Sensor 2
Video Lambda Sensor 3
Video Lambda Sensor 4
Video Lambda Sensor 5
Video Thermo Time Switch
Video Side-channel Pump
Video Peripheral Pump

Video First Fuel Pump
Video Petrol Injection Pump
Video D-Jetronic (MPI)
Video K-jetronic
Video KE-jetronic
Video KE-Jetroncic - Test, Diagn.
Video L-jetronic
Video LE-jetronic
Video LE-motronic
Video LH-jetronic
Video Vol. Air Flow Sensor
Video Idle Speed Device
Video Aux. Air Valve
Video Thermo Time Switch
Video Roller Vane Pump

Video Petrol injection 1
Video Petrol injection 2

          A B C D E F G H I J K L M N O P Q R S T U V W X Y Z



Although the air volume measurement did function, it had however, the disadvantages of the additional flap in the inlet manifold (loss of power) and the not always reliable mechanics of the rotary potentiometer. Apart from that, also an additional barometer was mostly necessary in the equipment for the altitude correction. All this was replaced by the air-mass meter. This was also the first time that a digital control device with a micro-processor was used.

How it works

In the LH-Jetronic a platinum hot-wire forms a resistance of a bridge connection, to which a temperature compensator in the slipstream, a precision resistance outside and an adjustable resistance also belong. This circuit is thus calibrated, that the temperature of the hot-wire always lies 100C higher than the outside air temperature. The air which is suctioned in, cools down the wire. Thus the applied current forms a measure for air-mass through-flow.

By the way, there were still, for a long time, vehicles which had to keep the volume air flow sensor. This could cope better with the pulsating air-mass. Only now can the repeatedly measured air-mass be deducted out again.In addition, the stupid auxillary air valve was finally replaced by a clocked, idling-filling regulator. It was switched on electronically within 1/100 of a second, in percentage, for as long as the bypass line should be opened. The sluggish armature or starter solenoid could not follow the commands that quickly and adjusted itself exactly to the percentage value. The line could be arbitrarily widely opened- or closed by the control device. Indeed, the times when the idling setting was done with a screwdriver were finally over. 09/09


Hot wire, Lambda sensor, temperature sensor (coolant), throttle switch, ignition signal (terminal 1)


Injection valve, relay (fuel pump), idling filling-regulator


Multipoint injection               Top of page               Index
2001-2015 Copyright programs, texts, animations, pictures: H. Huppertz - E-Mail
Translator: Don Leslie - Email:

Our E-Book advertising