Two problems related to engine belts and pulleys have been reported for the 2005 Audi A4. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Audi A4 based on all problems reported for the 2005 A4.
Noticed air bag lights on didnt think quick , also I notuced electrical issue here & there. Engine runs & sounds louder when using a/c. When you go to shut off vehicle theres a loud thump thump noise at the end fir about 3 mins or so , problems starting the engine , back windshield wiper turns on by its self , a week ago the light in the bavk turns on by it self. Other engine problems not sure if all tied in together I just started my purchase on 7/21/2020 from a car dealer. Had it checked by 2 people & one said air leak showing from diagnostic machine . My dealer put on machine & said didnt see nothing wrong. Power steering goes out have to fill almost every 2-3 days. My dealer said dont put more cause it could mess up engine. So I didnt & 2 days later driving 15 -20 mph on residential street it starts sounding like its going to stop so I presumed to shut off engine . Chevk under the hood & the power steering fluid was bone dey smoking slightly , & belt was pulled out a& shredded & it wouldnt even turm on enough to get a full start & dealer came & towed it back. Now he saying I need a new engine.
The timing chain (not the timing belt, which had been changed well before the recommended time) broke. This caused the engine to sieze immediate resulting in the car coming to a rapid and abrupt stop. Fortunately for me, it occurred at low speed on a very quiet street. Had it occurred on a freeway, serious injury or death likely would have resulted since the car decelerated so quickly I would not have had time to coast into the breakdown lane. Apparently failures of these timing chains occur commonly; Audi apparently has an extended warranty program for some cam follower wear problems (that may or may not involve a timing chain failure). But they do not list the chain or the follower as maintenance or inspection items, and give owners no hint that they should inspect the follower, or replace the chain periodically. Timing chain failures on zero clearance engines (vw has the same engine and apparently the same problem), will kill folks if they occur on freeways or other roads where an inability to coast to a safe stopping point will leave motorists at incredible risk.