You should change the air filter in your Carrera every 10,000 miles or so. The air filter protects the fuel injection system and the air intake system from dust and debris that can be sucked in under normal operation.
On the Carreras, the filter is just inside the air cleaner sitting in the engine compartment.
To access the 996 Carreras filter, simply release the 7 large Phillips head screws that hold the top of the cleaner to the bottom part of the housing, release the intake boot connection to the throttle body, unplug the MAF sensor and remove the oil filler tube from the housing. Take a look inside the filter housing—there are usually some leaves or dirt that found their way in there. Clean the housing out before installing the new filter.
To access the 997 Carreras air filter you must remove the complete airbox housing from the car, as the Torx screws that hold the top of the housing on are secured from the bottom of the housing. Loosen the clamp holding the intake to the throttle body, remove the mass sensor and its harness, if you have a 3.8 you will need to disconnect the wire from the vacuum resonator, free the oil fill tube from its clip and gently lift the complete housing from the car. The oil fill tube can break, so be careful when removing the airbox. Once the housing is out of the car remove the retaining screws from the bottom. Make sure to clean the inside of the housing before installing a new filter.
For the Carrera there are basically two different types of air filters—the stock paper or cloth air filters and aftermarket units. These aftermarket units utilize an oil-soaked fabric to achieve freer airflow. The bottleneck for airflow in the 911 Carrera engine is not necessarily the air filter. The primary advantage of the aftermarket units is that you usually only have to purchase one, and it will last the life of your car. No matter what your friends tell you, these aftermarket filters will not add any significant horsepower to your engine. Many tests on a dynamometer have revealed that the freer-flow air filters do not suddenly “create” horsepower out of thin air. If you install one of these filters into your car and “swear” there’s more horsepower, then have a friend do a blind test for you. Have him switch the filters in and out at random and see if you can tell the difference. This is what is commonly called the placebo effect—perceiving significant gains in performance just because you added a “performance part.”
The downside to using these aftermarket filters is that they often do not filter as well as the factory units. In addition, the use of aftermarket filters may cause excess dirt to accumulate in the mass airflow sensor and lead to its premature failure. The bottom line is that you need to carefully research any aftermarket filter before you install it into your car and carefully clean and maintain it thereafter. I personally prefer to use the stock OEM cloth/paper filters to ensure maximum filtering and protection. Whichever one you choose, make sure that it filters as well as or better than the original Porsche specifications.
The air filter is quite easy to get to on the 996 Carrera. From inside the engine compartment loosen the seven screws that hold the top of the air cleaner housing to the bottom (blue arrows). Then loosen the clamp that holds the intake boot to the throttle body (green arrow). Unplug the mass air flow sensor (yellow arrow) and the clips mounting it to the air box (purple arrows) unclip the oil filler tube from its home on the left side of the air cleaner housing. With everything disconnected, simply lift up on the housing to expose the air filter. The red arrow points to the bolt that holds the lower section of the air box to the chassis and does not need to be removed to change the air filter.
On the 997 Carreras, you will need to remove the complete airbox assembly to replace the air filter. The process is similar with the exception that there is a resonator switch installed in the air cleaner housing on the 3.8L engines. In order to remove the air cleaner housing, the cable plug must be disconnected from the electric switch over valve. This photo shows the airbox housing out of the car. The oil filler tube clip (red arrow) mass flow sensor (yellow arrow) and the throttle body clamp have all been removed or loosened. There are 8 Torx screws (blue arrows, three shown) that need to be removed to separate the airbox housings.
While you’re replacing the engine air filter, I recommend that you also swap out the cabin air filter as well. Sometimes known as a “pollen filter,” the cabin filter is located in the front trunk on the right side of the car. Remove the plastic panel just in front of windshield on the right side (upper left) with a T-25 Torx driver. Then reach in and pull out the filter. Install the new filter in place (upper right) and replace the plastic panel.
Comments: Thanks Nick. I managed it. Its such a tight quarter. A lot of ties and screws. Some people exaggerate the need to replace. I took out the original air filter after about 16,000 miles since new and it was OK but I still changed it- it really did not need it. I also took out a plug to see condition. It was like new so why do they tell you to change them at 10,000 miles? all the best
February 7, 2014
Followup from the Pelican Staff: Thanks for the follow up. We appreciate it. - Nick at Pelican Parts
Comments: about a month ago I tried to do this and gave up as that sensor connection would not unplug-do I need king kong fingers?
I will try again as the guys at the dealership will not be more refined than king kong.
February 2, 2014
Followup from the Pelican Staff: NO, you should be able to unclip it with normal fingers :). Sometime I find it helps if I push the connector toward the sensor while I press the release tab, then pull the connector off. - Nick at Pelican Parts
Comments: thank you nick.accurate info
January 26, 2014
Followup from the Pelican Staff: Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
Comments: i am going to replace air filter and pollen filter on my 2007 Carrera.
What torx set or sizes should I buy?
December 20, 2013
Followup from the Pelican Staff: This set will do what youn eed.
Comments: will i need to purchase a torx set to change the air filter?
December 5, 2013
Followup from the Pelican Staff: Torx drivers and sockets are essential if you're going to be doing your own work on the vehicle. - Nick at Pelican Parts
Comments: To unplug maas air flow sensor:
I found there is a slot on the back side to insert a flat head screw driver. Of course this is out of sight. Insert the screw driver into the slot and pull handle towards you and it should release.
November 30, 2013
Followup from the Pelican Staff: Thanks for the additional info. We appreciate it. - Nick at Pelican Parts
Comments: Thanks for the response, but I am still unable to get the plug to release - don't think it is a silicone problem - everything looks very clean and this car only has 8000 miles on it. Guess I will take it to the dealer unless you have any other suggestions.
November 17, 2013
Followup from the Pelican Staff: If you cannot get it to release by pressing the locking tabs and pulling it off, I am all out of ideas. - Nick at Pelican Parts
Comments: Still can seem to get the mass air flow sensor off
November 15, 2013
Followup from the Pelican Staff: Really shouldn't be that difficult. maybe someone used silicone to glue the connector on. - Nick at Pelican Parts
Comments: How the f do you unplug the maas air flow sensor?
November 9, 2013
Followup from the Pelican Staff: There are two tabs on the side of the connector. Squeeze them both at the same time and pull the electrical connector straight off. - Nick at Pelican Parts
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