Continuing our theme of making up for delayed maintenance tasks, today we tackle cleaning the throttle body. A dirty throttle body may affect throttle response and decrease gas mileage. For all 996s built after the 2000 model year with “e-gas” (throttle by wire) this task should take 30 minutes or less. For earlier cars with an actual throttle cable, the process isn’t really that much more complicated, but the throttle cable does have to be disconnected.

1. Disconnect intake hose and remove the airbox. (If you haven’t changed or cleaned your air filter in a while, this is a good opportunity to inspect the air filter as well.)
   
2. Inspect the throttle body before removing it. Look especially along the leading edge of the butterfly valve for crud buildup and any evidence of scoring or foreign object damage. Remove the four bolts indicated by the red arrows and disconnect the electrical connector at the top.
   
3. Inspect and clean the intake plenum. Look for foreign objects and excessive sludge. Clean as necessary.
   
4. Put the throttle body on your workbench and inspect both sides for build-up and damage. Clean using carburetor cleaner. Carefully open the butterfly valve manually to get to all of the areas needing cleaning.
   
5. Installation is the reverse of removal. Be sure to reconnect the electrical connector at the top. Clean throttle body looks almost brand new.