Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Electronic Control Unit (ECU)
The ECU of Audi models is found behind cover in front passenger footwell.
With ignition switched on, ECU is connected to battery voltage. To prevent voltage fluctuations when vehicle components are switched on, ECU is provided with voltage stabilizer circuit. Operating voltage is 8 volts.
ECU unit utilizes various input signals to control fuel delivery and control exhaust emissions. Output signals are sent to differential pressure regulator and to idle speed control valve.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.