The AUDI A4 (2001-05) 4DR SALOON 1.9 TDI 100 SPORT is a four-door diesel saloon in the UK’s mid-size executive-car class. Its separate boot, understated styling and roomy cabin make it a practical step up from a hatchback. It competed with the BMW 3 Series, Mercedes-Benz C-Class and Volkswagen Passat. Across 136 mycarcheck.com look-ups covering 46 VINs, examples averaged 158,000 miles and 9,000 miles annually, with nearly nine previous keepers. The average recorded private-sale valuation was £200; this is a check-data snapshot, not a current price guide. The figures describe cars checked, not every A4 on UK roads in general. The 1.9 TDI’s economy and comfortable ride suit commuters and small families, while the four-door layout provides useful space and a proper boot. Sport trim adds appeal, and it offers a refined alternative to mainstream saloons. Check service history and condition, given the high average keeper count in these checks.