IsItAGoodCar
Reliability Guide

Common Problems with the
2004 BMW Z4 (E85/E86)

We've identified 4 known issues that can affect the 2004 BMW Z4 (E85/E86). 1 of these are serious faults that could be expensive to repair.

4
Known Issues
1
Serious
3
Moderate
0
Minor

All Known Issues

Roof Motor Water Damage

SeriousBodywork & Rust

The electric roof motor is located in a drainage cavity that blocks with leaves and debris. The motor eventually sits in a pool of water and rusts solid.

Est. Repair Cost: £400–£800
Warning Signs:

Roof refusing to move when the button is pressed, Motor making a faint "struggling" sound but no movement, Manual release must be used to move the roof

What to Inspect:
  • Ask if the motor has been "relocated to the boot", which is the permanent fix
  • Check the drainage holes in the roof storage compartment for blockages
  • Test the roof operation several times in quick succession
Verified by IsItAGoodCar Research Team

Sticky Steering (EPS Column)

ModerateSteering

The grease in the electric power steering column can dry out or the components expand with heat, causing the steering to feel "sticky" or notchy on center.

Est. Repair Cost: £500–£1,000
Warning Signs:

Steering feels "stuck" when driving straight at motorway speeds, Small steering corrections feel notchy or require more force than normal, Problem gets worse as the cabin/engine bay warms up

What to Inspect:
  • Take the car for a long test drive to get it fully warm
  • Check for steering wheel corrections that feel inconsistent or lack "flow"
  • Ask if the steering column has been adjusted or replaced
Verified by IsItAGoodCar Research Team

Rear Coil Springs Snapping

ModerateSuspension & Chassis

The brittle rear springs often snap at the very bottom coil due to the car's weight distribution and UK potholes. It can be hard to spot without inspection.

Est. Repair Cost: £150–£300
Warning Signs:

Metallic pinging noise from the rear, One corner of the car sitting slightly lower than the other, Knocking over speed bumps

What to Inspect:
  • Shine a torch into the rear wheel arch and inspect the bottom coil of the spring
  • Check both sides, as they are usually replaced in pairs
Verified by IsItAGoodCar Research Team

DISA Valve Rattle (M54 Engine)

ModerateEngine

The flap inside the intake manifold (DISA valve) can work loose. If the metal pin falls out, it can be ingested by the engine, causing total failure.

Est. Repair Cost: £100–£250
Warning Signs:

Tapping or rattling noise from the intake side of the engine, Loss of low-end torque, Rough idling

What to Inspect:
  • Listen for a rattle from the black box on the side of the intake manifold
  • Unplug the DISA electrical connector while running to see if the rattle stops
  • Ask if an aluminium upgrade kit has been fitted
Verified by IsItAGoodCar Research Team

Buying Tips for 2004 BMW Z4 (E85/E86)

  • Check the soft-top roof operation; the hydraulic pump sits in a drainage channel that fills with water, corroding and destroying the pump.
  • Listen for 'ticking' from the N52 engine (2.5i/3.0i) on cold start, often caused by hydraulic lifters not getting enough oil during short trips.
  • Inspect the rear coil springs, as they frequently snap on the bottom coils due to corrosion and poor UK road surfaces.
  • Test the electric power steering (EPAS) on early models; a 'sticky' feeling dead ahead means the steering column requires replacement.
  • Check the cooling system expansion tank and radiator for leaks or bowing plastics, which must be replaced proactively.
  • Verify the condition of the front lower control arm bushes; wear here causes heavy tramlining and vague steering.
20032005
Check a 2004 BMW Z4 (E85/E86) by Registration