Audi Workshop Service and Repair Manuals

Notes:

• ◆ Renew defective tappets complete (tappets cannot be adjusted or repaired).
• ◆ When new tappets have been installed the engine must not be started for about 30 minutes (otherwise valves will strike pistons).
• ◆ 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 approx. 2 minutes: if necessary, perform road test.

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

• ‒ Remove cylinder head cover.
• ‒ Rotate crankshaft clockwise by turning securing bolt for toothed belt sprocket until the cams of the tappets to be checked are pointing upwards.

• ‒ Measure clearance between cam and tappet.
• ‒ → Push tappet down with a wooden or plastic wedge. If a 0.20 mm feeler gauge can then be inserted between camshaft and tappet, renew tappet if necessary: removing and installing camshafts and camshaft adjuster

Note:

If irregular valve noise occurs repeatedly during short journeys and disappears after extended driving, the oil check valves must be renewed => Page 17-12.