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

  Mass Air Flow Sensor 2

The pictures come from a piece of software, which can be downloaded for various testing devices from ''. It is necessary, that the testing device, in this case an oscilloscope, constantly extracts data and saves it in a format that is understandable for the software. The consecutive presentation of the tension lying on the air-mass flow sensor, is shown as a film.

The possibility of the comparison with other data is emphasised in several pages of Generally the workshop is satisfied with a multimeter measurement. Here, for educational purposes, it's quite clear, how many more possibilities there are for data-analysis, when using an oscilloscope.

BK Simmerath

In the 1st picture, the point is shown when the ignition is switched on. The achieved tension can be precisely determined, in each case in the second enlargement. In the 2nd picture, the engine is in the process of being started. Now, on the oscilloscope monitor, the respective RPM can be read out.

The first rotation of the engine through the starter motor lasts between 250 and 300 milliseconds. Because we're dealing with a four-cylinder, the time must be taken during two fluctuations, because then, two cylinders have taken in air (= 1 rotation). Multiplied by 1000 from milliseconds to seconds, and multiplied by 60 to minutes, give 150 to 180 starting RPM right from the beginning.

BK Simmerath

Picture three shows the actual starting of the engine, it can be seen by the increasing oscillation frequency, not as clearly by the air-mass. As before, the idling RPM can now be determined. In the fourth picture it becomes fascinating, because here we are dealing with a Diesel engine, whose Variable-Geometry Turbocharger now comes into action. The tension now rises somewhat more than the frequency.

BK Simmerath

At the moment we can't explain everything conclusively, e.g., the oscillations of the air-intake pipe. It is well known in the petrol engine with motion reversal on the valves and the throttle flap. Indeed, with a Diesel engine? Perhaps back-flowing air meets up with intake air. In the 6th picture, the partial oscillations can be observed even better.

BK Simmerath

In the 7th picture, we return to the completely normal idling without participation from the charger. Below you will still see the signal of a digital mass air flow sensor. Here, the frequency is changed exclusively by different rotational speed. One sees only the result, namely the increase in pressure. When the charger starts and whether there are vibrations in the intake manifold, thereof is nothing visible. 11/14               Top of page               Index
2001-2015 Copyright programs, texts, animations, pictures: H. Huppertz - E-Mail
Translator: Don Leslie - Email:

Our E-Book advertising