How to Change Spark Plugs on a Lexus Is

Step-by-Step Guide

1. 1

   Step 1: Remove the engine cover there are 4 bolts holding the cover.

   (4) 5mm allen screws are holding it down. , There will be 2 hose clamp it will be a 10mm bolt (mine has 2 if yours is stock you will have the on the top), loosen it.
   
   There will be a hose attached to the top tube by squeezing the clamp with your fingers wiggle it back and forth to get it off by pulling up towards the car.
   
   Pull the top of intake tube towards the left and it should come of fairly easy and the bottom pull upwards towards the car and it should come out.
   
   If it doesn’t come off easily unbolt the filter box and it should come off much easier. , There will be three connectors attached to the throttle body (1) above, left and bottom of the throttle body).
   
   The accelerator pedal position, throttle position sensor, throttle motor controller. , Rotate the throttle by hand so there will be a large amount of slack to the cable and remove it from the throttle body. , Loosen the driver side or passenger side and pull up to remove it. , There are (5) 12mm nuts attached to the throttle body and engine. 2 will be under the throttle body behind the wire.
   
   Snap the nuts to loosen as these will be on tight. , These are (2) 12mm bolts , There is a coolant hose attached to the throttle body.
   
   The hose shouldn’t be removed unless you intend on changing your coolant and bleeding the system.
   
   You can remove the hose if you want to; doing this will give you more room to work with.
   
   If you have removed the hose you should be able to slide the throttle body to the passenger side of the car. , There are (3) 12mm bolts holding on the gasket.
   
   Two are easy to get on the top and the third is positioned 7’0 clock on the gasket. , There are 3 harnesses attached to each coil.
   
   Push the tab and pull up, try not to pull on the wire while removing.
   
   If it comes difficult to remove use something soft to pry it loose.
   
   You will have access to (2) 10mm bolts holding the wire guide.
   
   Lift and move the harness wire away from the spark plug channel. , There will be 3 plugs wire on each plug that can be removed easily by pulling upwards.
   
   When removing the plug wires keep them in the relative position.
   
   There are (3) 10mm bolts holding each coil pack using an extension or a wobble joint and remove each coil.
   
   Again keep them in their relative position., Usually there will be a ton of road dust and debris in the channel.
   
   If desired, you can vacuum so dirt and other things won’t get into the engine.
   
   Remove each plug using a spark plug socket; the one closest to the fire will need a wobble head to get it out., Very carefully lower the plug attached to the socket into the hole.
   
   Do not drop it in you do not want to bend the gap between the electrodes.
   
   Once it has been seated tighten by hand be careful not to cross thread the plug, if it starts to get tight before 4 revolution back it out and try again.
   
   It should feel smooth all the way.
   
   You should be able to get 8 revolutions before you start to use the ratchet.
   
   Torque to 13ftlb.
   
   Installation is the reverse order.
2. 2

   Step 2: Remove the timing cover belt.

3. 3

   Step 3: Remove the intake tube.

4. 4

   Step 4: Review what you see.

5. 5

   Step 5: Remove the throttle cable.

6. 6

   Step 6: Use 2 14mm wrench to remove the cable from the cable support mount.

7. 7

   Step 7: Remove engine wire bracket.

8. 8

   Step 8: Remove the top 2 bolts on the throttle body.

9. 9

   Step 9: Check that the throttle body is free from the engine.

10. 10

    Step 10: Remove the throttle body gasket.

11. 11

    Step 11: Disconnect the engine harness.

12. 12

    Step 12: Remove plug wires and coil pack.

13. 13

    Step 13: Check that you can see 6 spark plugs.

14. 14

    Step 14: Install new plugs.

Detailed Guide

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