Checking Intake Air System For Leaks (Unmetered or False Air)

Intake System, Checking For Leaks (False Air)

Checking with engine leak detection spray

Recommended special tools and equipment
- Engine leak detection spray G 001 800 A1

Test requirement
- Coolant temperature must be at least 80 degree C, Diagnostic mode 1: Check measured values; PID 5, Coolant temperature. Engine Coolant Temperature Sensor, Checking

Test sequence

NOTE:
- Vacuum in the intake system sucks in the leak detection spray with false air. Leak detection spray decreases ignition quality of the fuel mixture. This causes a drop in engine speed and changes the value produced by the Heated Oxygen Sensor (HO2S).
- It is absolutely necessary to follow the safety precautions listed on the can.
- Connect diagnostic tester. Scan Tool Connecting
- Start engine and let run at idle.
- Under address word 33, select "Diagnostic mode 1: Checking measured values."
- Select the following measured values and check the specified values at idle.