Vehicle ignition system Audi A4 B5, petrol

Ignition system — general description
The ignition system, sending a spark in a timely and targeted manner, ensures the correct combustion process of the fuel-air mixture in the engine. And this...

When does the combustion of the fuel-air mixture occur?
The figure illustrates the concept of "Top Dead Center" and "Bottom Dead Center". The space between them is the working volume of the cylinder. On the...

Different ignition systems
The 74 kW engine is equipped with a Motronic ignition system with a distributor. In this engine, the ignition timing is adjusted, i.e. the ignition timing is...

This is how the ignition spark is created
The basic principle of ignition is that battery current first passes through the primary winding of the ignition coil. This winding consists of several turns...

Ignition system actuator
Output stage The final stage contains a powerful transistor, it switches the current to the ignition coil on and off (or to the ignition coils). Thanks to...

Ignition system control unit
Ignition and injection control are combined in one electronic unit. The ignition timing is also calculated there. The control unit has all possible engine data...

Signals coming to the control unit
Hall sensor Disassembled Hall sensor of the engine with a working volume of 1.8 liters. The most important parts are the integrated Hall system (in a housing...

Knock control
Detonation ignition, which occurs when the ignition timing is set too far in advance, is harmful to the engine and results in overheating, bearing damage and...

Be careful when handling ignition
In the engine compartment of the Audi A4, a sticker warns of high voltages in the ignition system, and for good reason: even in the thin wire to the ignition...

Work on the ignition system
Ignition stop The control unit and the final stage inevitably fail if the engine is turned over by the starter with the high-voltage wire disconnected....

Troubleshooting Ignition
Anyone who wants to identify a defect in the ignition must act according to the system: Whether there is an ignition spark at all can be determined by simply...

Ignition distributor
The distributor high voltage wires are connected to the spark plugs in accordance with the firing sequence in the 1.6L engine. The numbers indicate which...

High voltage unit
The high voltage unit of the ignition system, in addition to the ignition coil and distributor, includes the high voltage wire, the anti-interference connector...

Replacing spark plugs
To replace the spark plugs in a 92 kW engine, disconnect the connector (1) on the final power stage and unscrew the final stage together with the ignition...

Choosing the Right Spark Plugs
Candlestick Designations Using the designations in the table below, you will buy the right spark plugs for your Audi A4 model. What is hidden behind the...

Checking the ignition timing
In Audi ignition systems without a distributor, the ignition timing cannot be adjusted. In the case of distributor ignition with a 74 kW engine, the ignition...

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A4(B8, 2007-2015)

A4(B7, 2004-2008)

A4(B6, 2000-2006)

A4(B6, 2000-2006, petrol)

A4(B5, 1994-2001)

A4(B5, 1994-2001, petrol)