Service Training Audi 2.
Audi of America, Inc. Service Training Printed in U.S.A. Printed 1/2008 Course Number 921703 ©2008 Audi of America, Inc. All rights reserved. All information contained in this manual is based on the latest information available at the time of printing and is subject to the copyright and other intellectual property rights of Audi of America, Inc., its affiliated companies, and its licensors. All rights are reserved to make changes at any time without notice.
Table of Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 1 Engine Mechanicals . . . . . . . . . . . . . . . . . . . . 5 Oil System . . . . . . . . . . . . . . . . . . . . . . . . . 19 Crankcase Ventilation System . . . . . . . . . . . . . . 25 Cooling System . . . . . . . . . . . . . . . . . . . . . . 27 Air Intake System . . . . . . . . . . . . . . . .
Introduction
Introduction Technical Description Four Cylinder, Four Valve, FSI Turbocharged Gasoline Engine Engine Block – Cast Iron Crankcase – Balancer Shafts in Crankcase – Forged Steel Crankshaft – Sump-Mounted Oil Pump — Chain-Driven by Crankshaft – Timing Gear Chain — Front End of Engine – Balancer - Chain-Driven at Front End of Engine Cylinder Head – 4-Valve Cylinder Head – 1 INA Intake Camshaft Adjuster Intake Manifold – Tumble Flap Fuel Supply – Demand Controlled on Low and High-pressure Ends –
Introduction 2.
Notes
Engine Mechanicals Cylinder Block The cylinder block has a closed-deck configuration and is made of cast iron. It houses the five-bearing crankshaft assembly and the two balancer shafts. The housing for mounting the chain drives is integrated in the block. The cylinder liners are finished in a threestage fluid jet honing process. The undersides of the pistons are cooled by engine oil supplied by spray jets mounted on the cylinder block.
Engine Mechanicals Oil Pan The oil pan consists of two sections. The upper section is made of an aluminum alloy (AlSi12Cu) and reinforces the crankcase through a bedplate effect. It also houses the oil pump. The upper section is bolted to the crankcase and sealed with a liquid sealant. The bottom section is made of sheet steel (deep drawn, punched, and catalytically coated). It houses Oil Level Sensor G12 and the drain plug.
Engine Mechanicals Crankshaft The five main bearing crankshaft is made of forged steel and induction hardened. Optimal balancing is achieved by using eight counterweights. To additionally reinforce the crankshaft assembly, the three inner main bearing covers are cross-bolted to the cylinder block. Trapezoidal Connecting Rod (Small End) Material: 36MnVS4 Length: 5.82 in (148 mm) Big-End Bearing: 1.88 in (47.8 mm) Small-End Bearing: 0.82 in (21 mm) The crankshaft main bearings are a two component type.
Engine Mechanicals The chain drive sprocket is mounted to the crankshaft face and driven by a spur gear forged in the crankshaft. The other end of the chain sprocket also has a spur gear surface which drives the vibration damper. On the transmission side of the engine, a dual mass flywheel or torque converter (depending on transmission) is mounted to the crankshaft with eight bolts.
Engine Mechanicals Cylinder Head L M K N O J P I H Q G R F E D C S B T A 384_010
Engine Mechanicals The 4-valve cylinder head is cast from aluminum alloy. Intake and exhaust valves are actuated by roller cam followers supported by hydraulic valve lifters. The cylinder head cover adds support by acting as a ladder frame and does not have to be disassembled to remove the cylinder head. The intake and exhaust camshafts are chain-driven. The diagonal opening and sealing face simplifies drive chain installation.
Engine Mechanicals Bearing Bridge A die-cast aluminum bearing bridge mounted at the front of the cylinder head has the following tasks: – Supporting the Camshafts. – Supplying Pressurized Oil to Camshaft Bearings. – Supplying Pressurized Oil to Camshaft Adjuster. – Controlling Axial Movement of Camshafts. – Mounting Point for Camshaft Adjustment Valve 1 N205. The bearing bridge also serves to connect the two oil galleries of the cylinder head.
Engine Mechanicals INA Camshaft Adjustment System The 2.0L chain drive engine uses a hydraulic vane cell adjuster on the intake camshaft to affect valve timing. Only the intake camshaft has variably adjusted timing on this engine. Oil pressure for this task is provided by the engine oil pump. The variable camshaft adjuster provides an adjustment range of 60° crank angle. The camshaft is locked in the retard position at engine shut-off. This function is performed by a spring-loaded locking pin.
Engine Mechanicals Chain Drive Intake Camshaft with INA Adjuster 384_015 Balance Shaft Drive Gear Oil Pump Drive All three chains of the 2.0L engine are driven directly by the chain sprocket mounted to the crankshaft. The chains are arranged in three planes (levels). Gear chains are highly flexible in application because their width can be adapted for any power requirement by selecting the number of plates accordingly. They have an efficiency of approximately 99%.
Engine Mechanicals 1st Plane - Balance Shaft Drive Balance Shafts Guide Rail 384_016 Hydraulic Chain Tensioner Idler Gear Tensioning Rail Slide Rail Chain Sprocket Two cylinder block housed balance shafts are used to counteract unwanted vibration at engine speeds above 4000 rpm from being transmitted to the car body. Chain lubrication is provided by oil returning from the cylinder head. Oil is collected and distributed to the chain by a separate lubrication channel.
Engine Mechanicals Balance Shaft Layout Oil Return Channel from Cylinder Head Plastic Pipe 384_017 Oil Return Line The oil return channel from the cylinder head is located on the exhaust side of the cylinder block. Return oil flows through the balance shaft housing. The balance shaft is mounted in a plastic pipe. This prevents oil returning from the cylinder head from churning and foaming from direct contact with the balance shaft.
Engine Mechanicals 2nd Plane - Timing Gear Slide Rail, Timing Gear Chain Sprocket, Exhaust Camshaft Collar Bolt, Tensioning Rails Chain Sprocket, INA Intake Camshaft Adjuster Guide Rail, Timing Gear Tensioning Rail, Timing Gear Balance Shaft Gear, Exhaust Side of Engine Hydraulic Tensioner, Camshaft Chain Drive Balance Shaft Gear, Intake Side of Engine Tensioning Rail Chain Sprocket Slide Rail Balance Shaft Chain Tensioner Collar Bolt, Tensioning Rail Chain, Oil Pump Chain Sprocket, Oil Pump
Engine Mechanicals 3rd Plane - Oil Pump Drive Drive Sprocket Attached to Crankshaft for Oil Pump Slide Rail Oil Pump Oil Filter Screen Pressure Regulating Valve 384_021 The chain drive for the oil pump is located in the third plane. A polyamide slide rail is used in this drive to locate and tension the chain. The tension is produced by a mechanical spring. A hydraulically damped system is not needed due to the low dynamic load. The chain is lubricated by return oil or by the oil in the oil pan.
Engine Mechanicals Alternator/AC Compressor Drive A subframe supports both the alternator and air conditioning compressor. They are driven by a poly-vee belt which is tensioned by a spring-loaded tensioner.
Oil System Lubrication System Schematic Legend 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Screen Oil Pump, Chain-Driven Cold Start Valve Pressure Regulating Valve Check Valve, Integrated in Oil Pump Water-Oil Heat Exchanger Check Valve, Integrated in Oil Pump Oil Cleaner Oil Drain Valve Oil Pressure Switch F1 Spray Jets with Integrated Valves Oil Screen Chain Tensioner Chain Tensioner Gear Lubrication Coarse Oil Mist Separator Non-Return Valve,
Oil System 21 A A A A 27 A 18 B B B B B B B 19 B Vacuum Pump B B B A B B A B B A A B C D E B Camshaft Bearing Support Element Balance Shaft Bearing Connecting Rod Main Bearing A 17 Cylinder Head 14 13 28 Low-Pressure Circuit C D C 12 D D C D High-Pressure Circuit 12 E E 11 12 C E 11 12 C E 11 E 11 C Cylinder Crankcase 3834_024 20
Oil System Oil Pump The external gear oil pump is housed in the oil pan top section and is chain-driven by the crankshaft. Excessively high oil pressures can occur at high oil viscosity levels during cold starting. The oil pressure is controlled inside the pump by a control spring and piston. The system is also protected against overpressure by a spring loaded valve ball (cold start valve).
Oil System Oil Filter and Cooler The oil filter and oil cooler bracket are integrated in a subframe. It also houses the oil pressure switch and the tensioner for the belt drive. The oil filter cartridge is accessible from above for easy servicing. To prevent oil spillage when changing the filter, a breech pin opens as the filter is removed. This allows the oil to flow back into the oil pan.
Oil System Oil Filter Cartridge Oil Cooler Oil Feed from Oil Cooler Non-Return Valve Oil Flow to Engine Breech Pin Oil Seals Return Line to Oil Pan Closed in this Position Non-Return Valve Closed Sleeve Integrated in Oil Filter Breech Pin Resetting Range Allowing Direct Return To Oil Pan 384_027 23 Direct Return to Oil Pan
Notes 24
Crankcase Ventilation System System Overview In the 2.0L chain-driven TFSI engine, blow-by gases are vented from the cylinder block through the cylinder head cover. A fine oil separator is integrated in the cylinder head cover. A single-stage cyclone separator with a parallel bypass valve filters out any residual ultra-fine oil particles. An oil separator is installed on the cylinder block just below the engine coolant pump assembly.
Crankcase Ventilation System Positive Crankcase Ventilation This system supplies the crankcase with fresh air to mix with blow-by gases. Fuel and water vapors in the blow-by gases are absorbed by the fresh air and then discharged through the crankcase ventilation system. Fresh air is drawn in from the intake air system downstream of the air filter and Mass Air Flow Sensor. A breather pipe is connected to the cylinder head cover via a check valve (PCV valve).
Cooling System Engine Cooling System The engine uses a cross-flow cooling system. Engine coolant first flows to the front of the engine from the coolant pump. The coolant is then distributed along ducts and circulates around the cylinders. After circulating through the cylinder head, the coolant is routed back to the radiator via the thermostat housing or recirculated through the coolant pump if the thermostat is closed. The heat exchanger and turbocharger are part of the engine cooling circuit.
Cooling System Cylinder Head Cylinder Block Engine Oil Cooler Coolant Pump Drive 384_029 Thermostat Housing With Coolant Pump Outlet Long and Short Cooling Circuits Controlled By Coolant Thermostat Inlet 28
Cooling System Coolant Pump The coolant pump, temperature sensor, and coolant thermostat are integrated in a common housing made of duroplastic. Note The tension of the coolant pump drive belt is defined by the installation position of the coolant pump and cannot be adjusted. In the event of coolant pump failure, the housing must also be replaced. This housing is attached to the cylinder block below the intake manifold.
Notes 30
Air Intake System Intake Manifold Module Legend 1 2 3 4 5 Throttle Valve Control Module Intake Air Temperature (IAT) Sensor G42 Evaporative (EVAP) Emission Canister Purge Regulator Valve N80 Vacuum Motor for Intake Manifold Flap Changeover Fuel Port, High-pressure Pump 6 7 8 9 10 11 Fuel Port, High-pressure Fuel Rail Double Check Valve for Charcoal Canister System High-pressure Fuel Rail Fuel Pressure Sensor G247 Intake Manifold Flaps Intake Manifold Runner Position Sensor G336 3 4 2
Air Intake System The body of the intake manifold module is made of polyamide and consists of two shells which are plasticwelded together. Feedback about the flap position is provided by Intake Manifold Runner Position Sensor G336. When the engine is not running, the intake manifold flaps are closed. The intake manifold flaps are trough shaped. Through this shape and their arrangement in the intake port, the intake airflow is improved when the flaps are open.
Air Intake System Air Supply Vent Hose Turbocharger Vacuum Line Air Intake Intake Tube PCV Line Vacuum Pump Charcoal Cannister Line Air Filter Intake Manifold Runner Control (IMRC) Valve N316 Intake Manifold Vent Hose Oil Separator Pressure Regulating Valve Pressure Hose Charge-Air Cooler 384_032 33
Air Intake System Evaporative Emission System Venting of fuel vapors from the charcoal canister while the engine is running involves using two different paths. When boost pressure from the turbocharger is present, fuel vapors cannot directly flow into the intake manifold. In this case, the vapors are directed to the intake side of the turbocharger. When boost pressure is not present, the vapors are drawn in through the intake manifold downstream of the throttle body.
Air Intake System Vacuum Supply The required vacuum for the brake booster and other vacuum driven components of the engine is produced by a mechanically driven vacuum pump. For this reason, it is not necessary to use an additional vacuum reservoir. The pump is rated to deliver a continuous absolute pressure of 0.73 psi (50 mbar). The pump is a swivel vane pump driven by the exhaust camshaft and is installed behind the high-pressure fuel pump.
Air Intake System Vacuum Pump 384_064 The vacuum pump consists of a rotor running in bearings and a moving vane made of plastic which divides the vacuum pump into two sections. Vane The position of the vane is constantly changing due to the rotational movement of the rotor. As a result, the volume of one section increases while the volume of the other section decreases.
Fuel System Fuel System The fuel system is an advanced version of the system used on earlier TFSI engines. All parts which are in direct contact with fuel are designed in such a way that the engine can run on any available fuel grade. Special materials are used to ensure the fuel system meets all requirements relating to corrosion protection. The high-pressure system is supplied with fuel by a returnless, demand controlled pre-supply system. Fuel is delivered at a variable pressure between 50.7 psi (3.
Fuel System Fuel Rail The fuel delivery rate of the high-pressure pump has been reduced through the use of a four-lobe cam. A quicker pressure build-up is thus possible. This buildup benefits both cold start and hot start situations. Fuel Pressure Sensor G247 The fuel pressure sensor is mounted in the fuel rail and is designed for measuring pressures up to 2900 psi (200 bar). Note Always carefully follow the repair manual instructions when replacing the high-pressure fuel pump.
Fuel System High-Pressure Pump The demand controlled high-pressure pump by Bosch is driven by a four lobed cam on the end of the intake camshaft. The pump piston is driven by the camshaft and a cam follower. This reduces friction as well as the chain forces. The results are smoother engine operation and higher fuel economy. The use of the four lobe cam has allowed a reduced piston stroke compared to earlier versions of the 2.0L TFSI engine.
Fuel System Low-Pressure Damper Fuel Pressure Regulator Valve N276 Inlet Valve Delivery Chamber Needle Outlet Flange Coil Armature Piston Seal O-Ring 384_052 Pressure Limiting Valve Fuel Pump (FP) Control Module J538 Connection to Low Pressure Connection to Rail Note These cutaway views do not fully correspond to the originally installed pump.
Fuel System IV Delivery Chamber Delivery Chamber EV Intake Stroke IFRV Fig. 1 – Pump Piston Intake Stroke, Fuel Flows into Pump Chamber. – N276 De-energizes. – Intake Valve (IV) Opens Because Spring Force is Less than Flow Force of Transfer Fuel Pump - Vacuum is Present Inside Pump. 41 – Exhaust Valve (EV) Closes. Fig. 2 – Pump Piston Feed Stroke, Fuel Flows Back to Inlet. – N276 De-energizes. – IV Opens Due to Upward Motion of Pump Piston, Fuel Moves from Pump Chamber into Inlet.
Fuel System Delivery Chamber F Delivery Pressure F Flow force, EFP FRV De-energized F Spring The earlier N276 is activated, the more actively the delivery stroke can be used and hence the more fuel can be delivered. F IV F Delivery Pressure F Flow force, EFP F IV FRV Energized F Spring The operating point of the N276 changes depending on when it is activated by the engine control module. The “on” time remains the same.
Fuel System Injector Each fuel injector has six individual fuel openings, providing better mixture preparation. The angle of cone of the jet is 50°. These modifications have resulted in reduced HC emissions, particulate matter formation, and oil thinning. This also helps prevent “wetting” the intake valves and the combustion chamber surfaces during injection cycles.
Notes 44
Exhaust System Turbocharger and Manifold Module A turbocharger and manifold module is used. It is attached to the cylinder head by clamping flanges. Fuel Pump (FP) Control Module J538 Reference The exhaust gas turbocharger and manifold module, as well as the charge pressure control and the wastegate control system are described in SelfStudy Program 994503 - The 2006 Audi A3 Overview.
Notes 46
Engine Management System Overview of Bosch MED 17.
Engine Management System Actuators Motronic Engine Control Module (ECM) Power Supply Relay J271 Engine Component Power Supply Relay J757 Intake Manifold Runner Control (IMRC) Valve N316 Wastegate Bypass Regulator Valve N75 Fuel Pressure Regulator Valve N276 Fuel Pump (FP) Control Module J538 Transfer Fuel Pump (FP) G6 Cylinder Fuel Injectors 1-4 N30-N34 Ignition Coils with Power Output Stages N70, N127, N291, N292 Diagnostic Port Throttle Valve Control Module J338 with Throttle Drive (for Electronic
Engine Management System Engine Control Module The 2.0L TFSI engine uses the Bosch MED 17 engine control module. The hardware and software components have been developed so they can be used for future projects both for gasoline and diesel engine applications. This allows maximum use with regards to functions and vehicle interfaces independent of the engine combustion configuration. Examples of this include the Electronic Pedal Control and radiator fan activation strategies.
Engine Management System Substitute Functions in Case of Sensor/Actuator Failure Symptom in Case of Failure DTC Entry MIL EPC Substitute Signal Power Limitation Emergency Operation F63 No Cruise Control Yes No No No No No G39 No Control Yes Yes No Yes No No G61 No Yes No No Yes Yes No G62 No Yes Yes No Yes No No G83 Radiator Fan Runs Permanently in Setting 1 No No No No No No G79/G185 No Throttle Response Yes Yes Yes No Yes Yes G187/G188 No Throttle
Service Special Tools Shown Here are the Special Tools for the Chain-Driven 2.0 Liter 4V TFSI Engine.
Service 384_070 T10360 Torque Wrench Adapter Used for Removing/Installing the Belt Drive Pulley Bolt for the Engine Coolant Pump 384_071 V.A.
Knowledge Assessment Knowledge Assessment An on-line Knowledge Assessment (exam) is available for this SSP. The Knowledge Assessment may or may not be required for Certification. You can find this Knowledge Assessment at: www.accessaudi.com From the accessaudi.com homepage: –– Click on the “ACADEMY” Tab –– Click on the “Academy Site” Link –– Click on the ”CRC Certification” Link For assistance, please call: Audi Academy Learning Management Center Headquarters 1-877-AUDI-LMC (283-4562) (8:00 a.m.
Notes 54
921703 All rights reserved. Technical specifications subject to change without notice. Audi of America, Inc.
