During my last test drive with the 911s I had a CIS Flare up (figuratively) where after getting on it the car began running as if the mixture was lean (several small backfires) until the car stopped idling. It ran normally after restarting but I didn't hit the loud pedal as hard for the rest of the drive. Decided those symptoms pointed to an issue with the WUR. Well today was WUR investigation day. My WUR rebuild kit hadn't arrive but decided to pull it out and see what might be going on.
Once it was out it became very plain what the most likely culprit was.
Without new gaskets I wasn't 100% sure how to proceed. Gave the inlet mesh filter a blast of carb cleaner and it looked like this.
I couldn't believe how much cleaner the mesh filter looked. The expectation was the debris was imbedded in the mesh and would be difficult to clean. As I didn't have gaskets in hand I decided to clean the mesh with a few Q tips and more blasts of carb cleaner. Also gave the fittings which fuel lines attach to a thorough brushing up and slapped the WUR back in the car. No more backfire after giving it the beans. All in all a satisfying day turning wrenches on the 911.
Roger