Home › BMW 3 Series E90 / E92 / E93 › Water pump + thermostat

E90/E92/E93 · Reliability

E90/E92/E93 Water pump + thermostat

Your E90/E92/E93

Pick your year to see what fits.

This page covers the US sedan, coupe and convertible. It doesn't cover the 335d diesel or the E91 wagon.

Protects the engine
Hard$570–$6803–5 hrs
All E90/E92/E93 mods

Why do it

The 328i's electric water pump is a known failure point. Replacing it with the thermostat before it fails protects the engine.

Tools you'll need

Starting out? See our budget tool list.

Parts to buy

Double-check fitment before buying. We may earn a commission when you buy through these links, at no extra cost to you.

Before you start

  • The N52's electric water pump tends to fail without warning, and replacing it early protects the engine.
  • Work on a cold engine.

Steps

  1. Disassemble

    • Raise the car and remove the under panel and anything blocking the pump.
    Watch this step (Tomahawk813, on an N52 E90) (1:05–1:55)

  2. Remove the pump

    • Drain the coolant, unplug the pump and unbolt it.
    Watch this step (1:55–6:07)

  3. Remove the thermostat

    • Disconnect the hoses and remove the thermostat.
    Watch this step (6:07–11:12)

  4. Install the new parts

    • Fit the new pump with new screws and the new thermostat.
    Watch this step (11:12–14:40)

  5. Fill and flush

    • Refill the coolant and bleed the system.
    Watch this step (14:40–20:12)

How to know it worked

Did this guide work for you?

Safety first

  • Park on flat ground, set the parking brake and chock the wheels.
  • Never get under a car held up only by a jack. Use jack stands.
  • Let the engine and exhaust cool first.
  • Disconnect the battery before unplugging electrical parts.
  • Wear safety glasses.
  • If something doesn't match your car, stop and ask a shop.

Follow your part's instructions and your service manual's torque specs.