Changing the Air Filters on your DB9 is a pain in the ass. Swapping the filters themselves is easy (a 10 minute task), but there is a good deal of preparation work to tackle first. I’ve done posts and video’s on all the steps:
- Preparing a road wheel for removal
- Single point jacking of the car
- Putting the car on jack stands (optional since you can do one side at a time)
- Removing the front under tray (they say this is optional, but if you are in the middle of a full service you’ll have this off anyways)
- Removing the front inner wheel arch plastic fender liner (they say you can just remove a few screws and bend it back, but I’d rather remove it all).
Once you have access to the air box, it’s actually pretty simple. The only tools you’ll need are an 8mm 6-point socket and a 6″ extension and ratchet.
Crawl underneath and remove the seven (7) bolts that hold the air box cover. Once the screws are removed, separate the cover from the air box. I had to give it a few ‘thumps’ with my hand to break it loose.
With the cover off you’ll finally see the air filter. Grip the filter and wiggle it while pulling it down. It should come free with just a modest amount of effort – no tools required. Check out my video below.
Have a look at the bottom of the inside of the filter for a build up of engine oil. If you are finding a puddle of oil, you may have a classic issue with failing PCV valves that are allowing oil to be entrained into the crankcase ventilation, which flows back to the air inlet pipe on the front of the throttle bodies, and then it will drool back down the air inlet pipe and down into the bottom of the air filter.
I took the time to do a few things to the air box cover while it was off:
- I shook out the debris accumulated in the bottom (leaves and bugs).
- I checked that the white plastic button/valve was free to move (and rattle). I think this is a water drain.
- I checked that the groove around the edge was clear of debris.
- I wiped down the surfaces to make it look nice.
Now it’s time to fit the new air filter. Installation is pretty much reversal of removal process. Holding the air filter firmly, I pressed up and wiggled it to fit it back on the mount.
Next I refitted the air box cover, paying special attention that the groove around the edge mated properly with the rest of the air box.
Once in place, I reinstalled the seven screws. Don’t over tighten these, you are screwing into plastic. The official Aston Martin torque spec is 1.5-2.0 Nm. I don’t have a torque wrench that adjusts that low, so I just made them evenly snug.
I made a video of the process you can watch here.