Intake System, Checking for Leaks

Intake System, Checking for Leaks

Special tools, testers and auxiliary items required

• Engine Leak Detection Spray.

• 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° 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. => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the DTC memory. => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

3. If the DTC memory was erased, generate readiness code. => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.