BMW M3 CS common problems: what to check before you buy
Credov's researched list of the 5 faults the BMW M3 CS is known for (2000–2006), 5 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.
Known problems on the BMW M3 CS
M3/M4 fuel tank seam leak
Safety risk
2014–2020 · S55, S55B30 · petrol · Body and structure
What to look for: Smell for petrol around the rear of the car, and look underneath for damp or staining near the tank.
Why it matters: A leaking tank near a hot exhaust is a fire risk; typically NZ$3,000-$6,500 for a new tank.
2005–2006 · S54, S54B32 · petrol · Body and structure
What to look for: Check the sills at each jack pad and inside the rear wheel arch lips for bubbling or flaking rust.
Why it matters: Owners have had cars written off for jack-point and underbody rot; small surface bubbles are a paint job, but rotten jack points need cutting out and welding in repair sections, which is a structural repair, not cosmetic touch-up.
Got a question about a BMW M3 CS? Ask Credov: a noise, a warning light, a part or how to fix it.
Also check on every car
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.