Table of contents: Prerequisites for turbocharging… ↓ Consequences of a leak in the… ↓
Instructions: Observe the rules for maintaining cleanliness. Replace the cuff seals and self-locking nuts. The pressurization system must be airtight. The hoses and hose nipple of the air pressurization system must be cleaned of oils and grease before installation. Do not use lubricants under any circumstances. Use clamps of the appropriate series to secure all hose connections.
Prerequisites for turbocharging testing
Coolant temperature minimum 80°C. Engine control unit fault memory has been queried. EGR system is OK.
Instructions, If the EGR system is faulty, it is impossible to obtain reliable values during the turbocharger test.
No leaks in the intake and exhaust manifolds. The control line to the boost pressure valve is not clogged, loose, and tight. No engine or injection system problems, such as compression or unit injector problems.
Consequences of a leak in the supercharging system
A. leak in the area after the air flow meter "Q70"
Possible causes of malfunctions: 1. Connecting hose between the air flow meter "G70" and the turbocharger. 2. Connecting hose to the crankcase ventilation system. Consequence: insufficient power.
B. Leakage in the pressure line after the turbocharger (intake manifold area)
Possible causes of malfunctions: 1. Air duct hoses and pipes between turbocharger and intercooler, 2. Air duct hoses and pipes between intercooler and intake manifold, 3. Intercooler, 4. Seal under intake manifold pressure sensor "G71", 5. Seal between intake manifold fitting, mechanical EGR valve and intake manifold, 6. Seal between intake manifold and cylinder head. Consequence: boost pressure is too low.
C, Leakage after turbocharger (exhaust manifold area)
Possible causes of malfunctions: 1. Components of the exhaust gas recirculation system, 2. The connection of the exhaust manifold/cylinder head. Consequence: the boost pressure is too low, the smell of exhaust gases and traces of soot in the engine compartment may appear.
(The original text of the material can be found on the website AudiManual)