Oh, Audi. Why do you tempt us? The B5 S4 is, of course, the fairly hot version of the first-generation A4. To get any hotter, we'd have to stray into RS territory. But S seems like just the right amount of trouble to get into.
Europe had the S4 first, of course, a couple of years before the United States. That version was more powerful as well, because of not having to comply with federal emissions regulations. Thanks, big government. But 250 hp and 258 lb-ft of torque from that 2.7L twin-turbo V-6 (five valves per cylinder) is still fun, and 350 hp is a simple chip and exhaust system upgrade away.
The standard transmission is a six-speed manual, so clutches will be slippery when worn. A five-speed automatic transmission was an option, although other B5 S4 owners may never speak to you again. The all-wheel-drive setup we've come know and describe in a blanket fashion as "Quattro" didn't have crown gears or a torque-vectoring Sport Differential system, but simply the old-school Torsen hardware; no complaints about that.
Looks-wise, the B5 S4 is pretty pimping for an Audi, but still quite understated in the grand scheme of performance things. No complaints here, either. Some people don't like to shout. All things considered, this is a beautiful performance car with a dash of luxury. And it's a prime contender for all sorts of improvements, not just to the engine, but also to the handling. It's not, however, a car that can handle neglect.
The B5 S4 requires a simple approach to maintenance—just spend all your time and money on it, and you'll be fine. Let's start off with the basics. Perform regular oil changes every 5,000 miles and use good quality synthetic oil. Don't skimp on tires; it's amazing how much of a difference decent rubber makes—and this is a premium marque, for goodness sake.
The stock turbochargers will fail if they haven't already. If or when there's a need to replace them, an upgraded pair could easily boost engine output to 430 hp. This particular project will run to several thousand bucks, depending on choice of brand, shop, and how obsessive-compulsive you want to get. Mechanical sympathy is one easy way to make the ones currently under the hood last longer. Let them warm up before going nuts and let them cool down before turning off the ignition (ease up for that last mile or two).
In the cabin, the dot matrix display in the instrument binnacle will probably have dropped a few pixels. When it gets unbearable, there are replacements that are more reliable but also tend to be pricey. Leather upholstery is standard. Alcantara (the man-made faux suede material also used in the cabin) is great but hard to keep clean. Especially when there's grease from a hastily grabbed snack. Think about not eating and driving at the same time.
Maintenance history is paramount... and Universal, MGM, and Dreamworks all rolled into one. This is because the B5 S4 does not have a reputation for reliability. Common problems include (but are definitely not limited to) wheel bearings, spark plugs, coils, ignition control modules, diverter valves, rear main seal, valve cover gaskets, chain tensioner and gasket, and the coolant temperature sensor. Then there's the timing belt and water pump; unless they have been replaced recently by the current owner, bite the bullet and change them.
These cars are 16 years old or so, in which case a lot of them have already received some modifications. Don't be too afraid, but make sure they haven't been done by a monkey. If a seller is claiming big power, that could be a loud warning bell right there.
There's a ton of information on the web that will suggest many, many ways to spend loads and loads of cash. At one end of the spectrum is the "go for stage three straight away" school and at the other is the "upgrade components when they wear out" crowd. It's good to have a choice.
A hypothetical 2000 model with 138,000 miles (about average) in good condition and bought from a private party is blue-booked at $3,073. As ever, the real-life classifieds reveal sellers with a more optimistic view on life. We found a 2000 model with an aftermarket body kit and wheels, 92,000 miles on the odometer, and an automatic transmission going for $10,300. Slightly more tempting was a 2001 example with 114,000 miles with the timing belt and water pump changed (which sounds like the owner has been on top of the maintenance situation) going for $8,000. If you were looking at something cheaper, then still keep some money to one side for getting a few jobs done. And please have an expert cast an eye over it. With the right care and attention, the B5 S4 could be a wonderful method of personal transportation.