The Spark Plug Covers on a DB9 are used to shield both the Coil Packs and the Spark Plugs inside the valve cover.   All this is situated underneath the intake manifolds, so it’s a bit of a phaff to get to them.   You may need to remove the covers in order to change the Coil Packs or Spark plugs (like I am) or perhaps you are fixing a leaking valve cover gasket or something deeper in the engine.   Either way, it’s a pretty simple process.I’ve done a lot of work already getting to this point, including the steps detailed in these other posts and videos:

• Depressurizing your fuel system (so you don’t start a fire)
• Disconnecting your Battery (also so you don’t start a fire)
• Covering your fenders (so you don’t screw up your paint)
• Removing the Engine Bay Cross Braces (because it’s in the way)
• Removing the Intake Manifold Brace (because it’s in the way)
• Disconnecting the Fuel Rails and removing the Fuel Injectors
• Disconnecting all the other ancillary components attached to the manifolds
• Removing the Intake Manifolds

Tools Required

You only need a few things:

• T20 Torx Socket
• A suitable ratchet
• A suitable nut driver to make the process go faster

Process

If you have all the preliminaries noted above already out of the way this step only takes about 5 minutes per side.  Easy.

The official Aston Martin Workshop manual section on Spark Plugs covers it in step 2 “Remove the spark plug cover”.   Succinct.

Here’s my slightly more verbose version:

• All you really need to do it remove the ten (10) T20 Torx bolts per cover.  Way to go Aston, so you think 10 bolts was enough?
• Use your T20 Torx socket and ratchet to crack them loose, then use the nut driver to speed the process removing them (they are kind of long).
• Set the bolts and over aside, and be careful not to drop any of the bolts into the nearby intake inlets of V area of the block.
• Lift the cover away and set it aside.
• Repeat the process for the other side.

That’s it.   Not a ton of extra advice to add to this simple step.

Here is a quick video of the process to check out how it goes.