Audi Workshop Service and Repair Manuals

Special tools, testers and auxiliary items

• ◆ Feeler gauge
• ◆ Wood or plastic wedge

Notes:

• ◆ Hydraulic tappets cannot be adjusted or repaired.
• ◆ Irregular valve noises when starting engine are normal.

• ‒ Start engine and run until coolant temperature reaches approx. 80 °C.
• ‒ Increase engine speed to about 2500 rpm for 2 minutes (perform road test if necessary).

Note:

If the irregular valve noises stop but recur repeatedly during short journeys, a new oil retention valve must be fitted. The oil retention valve is located in the oil filter bracket .

If the hydraulic tappets are still noisy, locate defective tappets as follows:

• ‒ Remove cylinder head cover => Page 15-18.
• ‒ Rotate crankshaft until the cams of the tappets to be checked are pointing upwards:
• ‒ Vehicles with manual gearbox: push vehicle forwards with 4th gear engaged and ignition switched off.
• ‒ Vehicles with automatic gearbox: remove noise insulation and turn crankshaft clockwise by applying spanner to central bolt on crankshaft sprocket.
• ‒ Measureplay between cam and tappet.

• ‒ → Press tappet down with a wooden or plastic wedge. If an 0.20 mm feeler gauge can be inserted between camshaft and tappet, renew tappet.
• ‒ Renewing tappet=>Removing and installing camshafts and hydraulic chain tensioner / camshaft adjuster, Page 15-54.

Notes:

• ◆ Wait about 30 minutes after installing the camshafts before starting the engine. The hydraulic valve compensating elements must settle (otherwise the valves will strike the pistons).
• ◆ After working on the valve gear, turn the engine carefully at least 2 rotations to ensure that none of the valves make contact when the starter is operated.