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



Checking Intake System For Leaks (false Air)

Special tools, testers and auxiliary items required
- Engine Leak Detection Spray G 001 800 A1.
- Engine leak detection spray G 001 800 A1.

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 reduction in engine speed and a sharp increase of CO content.
- It is absolutely necessary to follow the safety precautions listed on the can.

Test requirements
- Coolant temperature at least 80 degrees C .
- The parking brake engaged.
- The selector lever of automatic transmission in position "P" or "N".
- The ignition switched off.

Test sequence
- Connect the diagnostic tester.
- Start the engine and let run at idle.
- Select "Mode 1: Checking measured values".
- Select the following measured values:







- Spray the intake system parts with engine leak detection spray in a systematic manner.

If the engine speed drops or if the short-term gasoline-air ratio changes:
- End diagnosis and switch the ignition off.
- Check the sprayed part of intake system for leaks, and repair the malfunction.

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.

- End diagnosis and switch the ignition off.