Credov's researched list of the 3 faults the Audi RS4 is known for (2006–2008), 3 of them serious or costly. Each one says what to look for when you check the car, so you can spot it before you buy. Not every car has these faults: they are the ones worth checking on this model.
What to look for: At cold start, feel for a lumpy, shaking idle in the first minute that smooths out as it warms.
Why it matters: Heavy carbon build-up on the intake valves steadily robs this V8 of power and can cause misfires, and clearing it means removing the intake manifold to blast the valves and ports clean, which is a specific and not-cheap job.
What to look for: Look behind each wheel with a torch for oily damper bodies, and push down on each corner to check it settles.
Why it matters: Leaking DRC dampers affect handling and ride quality and the complete system is a specific and costly replacement, so knowing whether it still has factory DRC, and whether it leaks, changes both the car's handling and its price.
What to look for: On the drive, pull away gently, reverse up a slope, and watch for jerks or a transmission warning.
Why it matters: A mechatronic failure on this gearbox can cause a sudden, unexpected loss of drive while on the road, and the unit itself is an expensive specialist replacement, so any warning message or shift fault on the test drive is a serious finding.
Got a question about a Audi RS4? Ask Credov: a noise, a warning light, a part or how to fix it.
On top of the faults above, every Credov inspection covers the basics: fuel smell, leaks or filler rust, engine oil leaks, power steering fluid leak, drive belt cracks or squeal, rust underneath: chassis and mounts, engine mounts, engine oil level and colour, coolant level, colour and leaks, head gasket failure signs, cold start: rattle, knock or smoke, rough or hunting idle, engine running hot on gauge, gearbox or diff oil leak, swapped gearbox without lvv and more.
Researched by Credov from manufacturer recalls and service bulletins, owner reports and workshop sources. Repair prices are typical ranges, not quotes. See also fault codes and repair costs.