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S4 Spark plugs

Your S4

Pick your year to see what fits.

This page covers US S4s only. The S5 has its own page.

Restores lost power
Medium$60–$1701–3 hrs
All S4 mods

Why do it

Worn plugs cost power and throttle response. Fresh plugs bring the punch back.

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

  • Torque from the video: 22 ft-lb.
  • Work on a cold engine. Do one plug at a time.
  • Work on a cold engine. Do one plug at a time.
  • Work on a cold engine. Do one plug at a time.

Steps

  1. Remove the air intake and filter housing

    • Take off the intake and filter housing for room.
    Watch this step (on a 2001 S4 2.7T) (1:48–2:30)

  2. Swap the plugs

    • Pull the coils, take out each plug and torque the new one.
    Watch this step (2:30–4:45)

  3. Refit the coils

    • Push the coils back in and plug them in.
    Watch this step (4:45–5:35)

  4. Get to the plugs

    • Take off the engine covers and what's in the way.
    Watch this step (TRQ, on a 2006-2009 S4 4.2L) (0:00–1:54)

  5. Swap the plugs

    • Pull each coil, swap the plug and refit the coil.
    Watch this step (1:54–4:26)

  6. Put it all back

    • Refit everything.
    Watch this step (4:26–8:03)

  7. Remove the cover and intake scoop

    • Take off the engine cover and the intake scoop.
    Watch this step (on a B8/B8.5 S4) (0:40–1:25)

  8. Remove the intake hose

    • Take off the hose to make room.
    Watch this step (1:25–2:09)

  9. Move the coolant tank

    • Unbolt the tank and move it aside. Don't disconnect the hoses.
    Watch this step (2:09–2:43)

  10. Remove the coil harness screws

    • Undo the screws holding the harness.
    Watch this step (2:43–4:05)

  11. Remove the coils

    • Unplug and pull each coil.
    Watch this step (4:05–5:11)

  12. Remove the plugs

    • Unscrew each old plug.
    Watch this step (5:11–5:47)

  13. Fit the new plugs

    • Start each new plug by hand, then torque it.
    Watch this step (5:47–6:38)

  14. Put it all back

    • Refit everything and start the car.
    Watch this step (6:38–7:07)

  15. Remove the air box

    • Take the air box out.
    Watch this step (on a B9 S4) (0:51–2:11)

  16. Pull the passenger side coils

    • Unplug and pull each coil.
    Watch this step (2:11–3:38)

  17. Swap the passenger side plugs

    • Unscrew each plug, start the new one by hand and torque it.
    Watch this step (3:38–5:35)

  18. Refit the passenger coils

    • Push the coils in and plug them back in.
    Watch this step (5:35–7:02)

  19. Pull the driver's side coils

    • Do the same on this side.
    Watch this step (7:33–9:28)

  20. Swap the driver's side plugs

    • Change each plug the same way.
    Watch this step (9:28–10:25)

  21. Refit the coils and air box

    • Put the coils and air box back.
    Watch this step (10:25–13:44)

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.