5-speed manual transmission flushed with new fluid at 103k miles. Transmission makes grinding noise only on 1st gear because previous owner had never flushed the transmission fluid as required every 25k miles.
Outer tie-rod ends were replaced at 103k miles. Worn out tie-rod ends causes excessive vibrations while driving. Replacements cost $100.
Original head-unit malfunctioned at 104k miles. New Pioneer head-unit installed.
Sunroof controls are malfunctioning at 103k miles. Sometimes it will close and other times it stays partial open. Replacement cost $150.
Thermostat was replaced at 104k miles. Original thermostat was stuck in open position causing bad fuel economy. Replacement cost $30.
Brake and clutch system flushed with new fluid at 104k miles. Required every 2 years.
Power steering system flushed with new hydraulic fluid at 104k miles. Previous owner flushed with regular power steering fluid! Audi requires use of hydraulic fluid for power steering!
Both catalytic converters rattle loudly at 108k miles. Replacement cost $500 each because only the catalytic converters from the dealership will be C.A.R.B. legal in California.
C.V. boots cracked open on both front axles at 110,000 miles. Both axles were replaced with rebuilt axles. Replacements with core exchange cost $100 each.
Dashboard warped along the edge that is touching the windshield. This occurs if it was exposed to excessive heat from hot summer days. Sun-shields should be used when A4 is parked in direct sunlight.
Unknown location of water leak on drivers side floor during heavy rains. Possibly leaks from the rubber sealing the hood latch cable housing.
Randomly an instrument cluster bulb burns out. Replacement cost $3 per bulb.
Interior dome light switches all fell out. Poor design renders useless interior lighting.
Climate control LCD screen flickers on/off randomly. Just a poorly designed electrical connection for the LCD screens. tapping around the edges of the screen temporarily fixes the flickering when it occurs.
Factory alarm module removed. Alarm would go off randomly whenever the A4 was parked on uneven surfaces.
Low RPM vibrations felt inside cabin during cruising speeds around 30-50mph. This is caused by the back pressure of the exhaust system. Occurs in most A4's with factory exhaust system because 2 mufflers are utilized in conjunction, not separately.