The engine in the 1993 Audi 100 is an interference engine, which means that should the timing belt stretch too much or break, it could cause excessive engine damage, yet the manufacturer has not determined an exact time — whether mileage or a time frame — to change the belt. Experienced mechanics recommend changing the timing belt every 60,000 miles. Belts are made of rubber, which does stretch over time, but an automatic tensioner controls tension on the belt. Once the tensioner reaches its stop, it can no longer tension the stretching belt.
Tools Used: Tools, Set of sockets, Camshaft holding tool No. 3243, Crankshaft holding tool No. 3242, 8 mm Allen wrench, Torque wrench
Install Timing Belt
Fit the appropriate socket onto the bolt in the center of the accessory drive belt tensioner. Rotate the tensioner away from the belt to loosen the belt tension. Lift the belt off the pulleys. Remove the belt tensioner, using the appropriate socket. Unclip the left and right timing belt covers.
Turn the crankshaft clockwise until the timing mark on the crankshaft pulley lines up with the mark at the 12 o’clock position. The large holes in the camshaft sprockets should be facing each other — the left sprocket’s hole — as you are looking down at the engine — should be at 3 o’clock, and the right sprocket’s hole should be at 9 o’clock.