2003 vs 2004 BMW Z4

vs

Both years are the same generation, so most of what they offer is shared.

Watch out for

Reputation: what owners and the press report. Tap one to see what to check.

2003

Nothing that 2004 lacks.

2004

Nothing that 2003 lacks.

Both years

  • Power top motor drowned by the roof drains All years

    What to check: Run the power top up and down several times. A slow or stalling roof points to a tired motor. Ask whether the motor has been moved into the trunk, and clear the roof drains.

    Eight owners in four threads on a British owners' forum say the power top's motor sits where water from blocked roof drains collects and fails; several had theirs moved into the trunk, which they call the fix. An Edmunds owner review says the same, and Euro Premium Parts lists motor failures on high-mileage roadsters. One forum owner says a US car may have had a manual top as standard.

    Edmunds, owners' reports (unofficial), a seller's guide (unofficial)

  • Broken rear springs and worn suspension All years

    What to check: Look at the rear springs for a broken coil and listen for knocks over bumps. Ask when the springs, dampers and front control arm bushings were last renewed.

    Three owners in one thread on a British owners' forum say the rear springs break, one that it happens on most cars over five years old, and two owners in another thread say to budget for new dampers and a suspension refresh. Euro Premium Parts says worn front control arm bushings are almost universal past 70,000 miles.

    Owners' reports (unofficial), a seller's guide (unofficial)

  • Cooling system failures All years

    What to check: Ask when the water pump, thermostat and expansion tank were last renewed, look for coolant leaks and watch the temperature gauge on a long drive.

    Euro Premium Parts says the plastic thermostat housing and expansion tank crack with age, and that the N52's electric water pump can fail without warning. Seven owners in two threads on a British owners' forum name the facelift cars' water pump or a leaking expansion tank or radiator.

    Owners' reports (unofficial), a seller's guide (unofficial)

  • Oil leaks from the valve cover and oil filter housing All years

    What to check: Look for oil around the valve cover, the oil filter housing and under the car.

    Five owners in three threads on a British owners' forum report leaks from the valve cover or oil filter housing gaskets as the rubber ages, and Euro Premium Parts says the oil can drip onto the exhaust.

    Owners' reports (unofficial), a seller's guide (unofficial)

  • DISA valve and crankcase vent on the M54 2003–2005

    What to check: Ask whether the DISA valve and the crankcase ventilation valve have been replaced, and listen for a rough idle.

    Four owners in two threads on a British owners' forum name the M54's DISA intake valve, one warning that a failed one can destroy the engine, and one says the crankcase vent suffers in cold weather and on short trips. Euro Premium Parts calls a clogged crankcase vent a frequently overlooked item.

    Owners' reports (unofficial), a seller's guide (unofficial)

  • Corroded brake lines All years

    What to check: Look under the car at the rear brake pipes, where the plastic cover ends and road dirt builds up.

    Three owners in three threads on a British owners' forum report rusted brake lines, one after a leak, and one says the rear pipes rot where dirt collects at the end of their cover.

    Owners' reports (unofficial)

  • Failing window regulators All years

    What to check: Run both windows up and down a few times.

    Two owners in one thread on a British owners' forum say the window regulators fail often, and Euro Premium Parts says they fail on the roadster in particular.

    Owners' reports (unofficial), a seller's guide (unofficial)

Recalls

2003

  • 03V032000 2003

    The link between a front seat belt buckle and its tensioner's steel cable may not meet BMW's specification and can come apart in a severe frontal crash. Dealers inspect both sides and replace parts as needed. NHTSA

  • 03V214000 2003

    A tire may have been damaged when it was mounted on the wheel. Dealers unseat and inspect the tires and replace a damaged front tire. NHTSA

  • 04V247000 2003

    An incompatible airbag control processor may have been fitted. Dealers inspect and replace it if needed. NHTSA

2004

Nothing that 2003 lacks.

Both years

  • 04V182000 2003–2004

    In some conditions vapor lock in the fuel pump can stall the engine, which then will not restart for about 15 to 20 minutes. Dealers add a resistor to the fuel pump's power line. NHTSA

What changed between

After 2003, up to and including 2004.

  1. 2004Rain-sensing wipers and automatic headlights become standard, and BMW Assist and a removable hardtop are new options. Edmunds, CarGurus

What it came with

2003

Nothing that 2004 lacks.

2004

Nothing that 2003 lacks.

Both years

Engines
2.5L inline-six (2003–2005) Edmunds, a published reference, 3.0L inline-six (2003–2005) CarGurus, a published reference
Transmissions
Five-speed manual (2003–2005) Edmunds, CarGurus, Six-speed manual CarGurus, Edmunds, Five-speed automatic (2003–2005) CarGurus, a published reference, Six-speed SMG automated manual (2003–2005) Edmunds, CarGurus
Drivetrains
Rear-wheel drive Edmunds, a published reference
Body styles
Roadster Edmunds, a published reference
Packages
Sport Package CarGurus, Edmunds

What owners and buyers say

Reputation: what owners and the press report

2003

Nothing that 2004 lacks.

2004

Nothing that 2003 lacks.

Both years

  • Watch for: An early car with the SMG gearbox 2003–2005 Less sought after One source so far

    CarGurus says early cars with the SMG shifted poorly and are not recommended for reliability. CarGurus