Audi A4 Sedan, Avant, Cabriolet Repair Manual 2002-2008

The do-it-yourselfer is faced with a number of options when purchasing a rebuilt engine. The major considerations are cost, warranty, parts availability and the time required for the rebuilder to complete the project. The decision to replace the engine block, piston/connecting rod assemblies and crankshaft depends on the final inspection results of your engine. Only then can you make a cost effective decision whether to have your engine overhauled or simply purchase an exchange engine for your vehicle.


SOME OF THE REBUILDING ALTERNATIVES INCLUDE:

INDIVIDUAL PARTS. If the inspection procedures reveal that the engine block and most engine components are in reusable condition, purchasing individual parts and having a rebuilder rebuild your engine may be the most economical alternative. The block, crankshaft and piston/connecting rod assemblies should all be inspected carefully buy a machine shop first.

SHORT BLOCK. A short block consists of an engine block with a crankshaft and piston/connecting rod assemblies already installed. All new bearings are incorporated and all clearances will be correct. The existing camshafts, valve train components, cylinder head and external parts can be bolted to the short block with little or no machine shop work necessary.

LONG BLOCK. A long block consists of a short block plus an oil pump, oil pan, cylinder head, valve cover, camshaft and valve train components, timing sprockets and belt or gears and timing cover. All components are installed with new bearings, seals and gaskets incorporated throughout. The installation of manifolds and external parts is all that’s necessary.

LOW MILEAGE USED ENGINES. Some companies now offer low mileage used engines that are a very cost effective way to get your vehicle up and running again. These engines often come from vehicles that have been totaled in accidents or some from other countries that have a higher vehicle turnover rate. A low mileage used engine also usually has a similar warranty like the newly remanufactured engines.

Give careful thought to which alternative is best for you and discuss the situation with local automotive machine shops, auto parts dealers and experienced rebuilders before ordering or purchasing replacement parts.

VARIABLE INTAKE MANIFOLD: COMPONENT REPLACEMENT: 2.0L FOUR-CYLINDER MODELS

Refer to illustrations 19.4, 19.5 and 19.8

WARNING: Wait until the engine is completely cool before performing this procedure.

1. Remove the engine cover.
   
   
2. Remove the coolant expansion tank (see Chapter 3).
   
   
3. Remove the air intake hose between the left intercooler and the throttle body (see Chapter 4).
   
   
4. Remove the two fasteners (see illustration) that secure the electrical connector bracket to the coolant pipe.
   
   
5. Disconnect all electrical connectors from the area adjacent to the intake flap motor (see illustration).
   
   
6. Cut the cable ties that secure the wiring harnesses to the coolant pipe, move the harnesses out of the way and remove the connector bracket.
   
   
7. Remove the bolt that secures the coolant pipe bracket (see illustration 19.5) and push the coolant pipe out of the way.
   
   
8. Using a screwdriver, disengage the intake flap motor control rod from the crank arm on the intake manifold (see illustration).
   
   
9. Remove the intake flap motor mounting fasteners and remove the motor.
   
   
10. Installation is the reverse of removal.

Introduction: About this manual | Introduction | Vehicle identification numbers | Maintenance techniques, tools and working facilities | Buying parts | Jacking and towing | Booster battery (jump) starting | Conversion factors | Automotive chemicals and lubricants | Safety first! | Troubleshooting

• Tune-up and routine maintenance
• 1.8L 4-cylinder turbocharged engine
• 2.0L 4-cylinder turbocharged engine
• 3.0L V6 engine
• 3.2L V6 engine
• General engine overhaul procedures
• Cooling, heating and air-conditioning systems
• Fuel and exhaust systems
• Engine electrical systems
• Emissions and engine control systems
• 5-speed manual transmission
• 6-speed manual transmission
• 5-speed automatic transmission
• 6-speed automatic transmission
• Continuously Variable Transmission (CVT)
• Driveline
• Brakes
• ABS
• Suspension and steering systems
• Body
• Chassis electrical system
• Wiring diagrams