Variable Induction System: Testing and Inspection

Intake System, Checking for Leaks

Special tools, testers and auxiliary items required

• Engine Leak Detection Spray (or equivalent)

• All manufacturer's special tools as well as common tools may contain a manufacturer specific part number. These tools may be substituted with an equivalent aftermarket tool, or are available for purchase from the manufacturer.

• Manufacturers special tools as well as common tools that contain a manufacturer specific part number may be referenced in the test procedure illustrations, showing the tool use or installation. If the manufacturer specific tool is not being used, an equivalent aftermarket tool may be installed in the same manner as the manufacturer's special tool.

• 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 procedure

- Perform a preliminary check to verify the customers complaint. Refer to --> [ Preliminary Check ] Preliminary Check

Start diagnosis

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. Refer to --> [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

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

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

- End of diagnosis.