Checking Air Intake System For Leakage

Check that all hoses are undamaged and in place with hose clamps tightened.
Disconnect fresh air hose from MAF sensor. Install Volvo adapter (999 5545) with pressure regulator (999 5544) on fresh air hose and tighten hose clamp. See Fig 1.
Clamp crankcase ventilation hose with hose clamp. Remove oil filler cap. Remove lower hose from canister purge valve.

NOTE: Opening of intake valve and leakage of cylinder pressure past piston rings will cause gentle hissing sound from oil filler opening.

Connect compressed air hose and adjust regulator to obtain a maximum pressure of 4.35 psi (0.3 bar).

NOTE: Bubbles are permitted around throttle spindle and between throttle body and plastic intake hose. If intake hose is rubber, bubbles are not permitted.

Check components (A-V). See Fig 2. Check connectors (A-G). See Fig 3. If leak is suspected, spray soap solution onto area of suspected leak to find where air is escaping from. Repair as necessary.

Fig 1: Connecting Adapter (999 5545) & Regulator (999 5544)

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Intake System Components

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 3: Identifying Intake System Connectors

Courtesy of VOLVO CARS OF NORTH AMERICA.