Credov's researched list of the 8 faults the BMW 3 Series is known for (2005–2013), 8 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: Check the airbag warning light goes out after start-up, then watch it with someone sitting in the passenger seat.
Why it matters: A disabled passenger airbag is a real safety gap in a crash, and it is a cheap fault to find before you buy; typically NZ$500-$1,500.
What to look for: Look under the gearbox for wet fluid around the sump pan and the wiring plug sleeve.
Why it matters: A small sleeve or pan leak is cheap to fix early, but a box run low on fluid can need a rebuild; typically NZ$500-$5,000 depending on how far it has gone.
What to look for: On the test drive watch the temperature reading and the dash for a coolant or overheating warning.
Why it matters: The pump fails with no warning and driving on can warp the head; typically NZ$1,200-$2,800.
What to look for: On the test drive accelerate hard in 3rd and 4th watching for a power warning, and note long cold-start cranking.
Why it matters: A failing pump can shut the engine down while driving, and pumps have failed more than once on the same car; typically NZ$1,500-$3,000.
What to look for: Accelerate to about 3,500 rpm, lift off, and listen for a metallic rattle from the right side of the engine.
Why it matters: Unmanaged boost and a failed wastegate usually means two new turbos, engine out on some cars; typically NZ$5,000-$12,000.
What to look for: In iDrive check the oil level reading works, and watch the dash for oil pressure or oil level warnings.
Why it matters: Sudden oil pressure loss on a direct-injection six can wreck the engine; repairs commonly run NZ$3,000-$15,000.
What to look for: Cold start and listen at the gearbox end of the engine for a rattle or whine.
Why it matters: A snapped chain wrecks the engine and needs the engine out; typically NZ$5,000-$12,000.
What to look for: Press the passenger carpet near the kick panel for damp, and check for a musty smell.
Why it matters: A long-term leak sits under modules and wiring in the footwell, causing electrical faults, a musty smell and rusty seat rails, and the entry point is cheap to miss on a quick look.
Got a question about a BMW 3 Series? 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.