2004 Audi S4 B6 Fuel Door Actuator Replacement
 

Part: 8E0 862 153 (can purchase for around $30 USD)

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1. Remove the interior trunk carpet lining on the fuel door side of trunk. These are held in by a set of metal and plastic clips. The inner compartment molding that has a bungee rail to hold stuff also has plastic clips that will pop out when you start to pull out the lining. Note: I didn't completely remove the lining , I only released the clips to expose the area by the fuel door. Once the lining is removed, you can pull it back to see/access the actuator that's attached to a metal body piece


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2. Look at the first picture: You can see the actuator has two 1/8" hexagonal screws with Phillips screw heads. The Phillips heads sit at the BACK of the actuator and face away from your view. These slide into keyhole slots on the metal plate. You can see the keyhole slots that hold that actuator in place in the picture above

3. The actuator has a cable that is attached to the top by a plastic clip. You can remove this by squeezing two plastic pieces with you fingers on each side. You should then be able to free the clip. Note: You can clip in your new actuator at this time and press lock/unlock on your key FOB to make sure the new unit works. I'd recommend this to save you time if there is a problem with the new unit


4. The back of the screws ( the hexagonal side) face out towards you. The key is these DONT have to be completely removed. I used a crescent wrench adjusted to fit snugly on the screw and a set of pliers. Since your looking at the back of the screw, you'll twist them CLOCKWISE to loosen them. You will hear the squeaking of the plastic when it twists. Loosen each screw until each side gives and you feel the play as it loosens from the keyhole. You can then SLIDE the actuator to the LEFT and out of the keyhole molding. You can then slide the metal pin out of the hole and pull the unit out.

5. A challenging part is getting the metal pin back into the fuel door pinhole. You'll have to see where the pin lines up from the inside and use your finger on the outside to feel for the pin hole. You could feed a string through the hole and tie it to the pin to help guide the pin through. Once the pin is in place, set the actuator screw heads in the large part of the keyholes and slide the unit to the right to set the screws in place. Hold the unit in place and carefully tighten the hexagonal side of the screws by turning COUNTER CLOCKWISE until it is snug.