Checking Intake System For Leaks (False Air)
Special tools, testers and auxiliary items required
- Engine Leak Detection Spray.
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 scan tool.
- 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 the repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.
- End of diagnosis.