If you’ve ever been unable to fill your 2002 Carrera 4S with gasoline, you’re not alone.  While online discussions often revolve around the E6 fuse, however in this case it was not the case but we’re going to go into detail about the E6 fuse and what it does.

The customer’s complaint was straightforward – they couldn’t get gasoline into their car. Despite visiting three different gas stations with the reserve light on, their attempts were in vain. Initial online research often points to the E6 fuse, a common topic in fueling issues. However, our investigation took us in a different direction.

The filler neck, the pathway for fuel from the gas cap to the tank, revealed a critical detail. A revision in the design included a new splashback valve, addressing potential problems. The splashback valve plays a crucial role in preventing fuel from splashing out during the filling process. Our attention was drawn to the canister shut-off valve, which, when malfunctioning, led us to further explore the components involved.

The gas cap proved to be a pivotal element in the fueling process. A tiny button switch on the cap interacts with the fuel system, controlling valves that open and close during tightening and removal. This mechanism ensures proper venting of air from the tank during fueling, preventing backsplash. A vivid account of a fueling mishap at a gas station highlighted the severity of the issue.

Evaluating the E6 Fuse and Components:
Contrary to expectations, the E6 fuse wasn’t the culprit in this case. Our focus shifted to a faulty vent valve and solenoid, components critical for the fueling process. Bench testing and a meticulous examination of the vent valve revealed the source of the problem. It was an intricate process, but the determination to fix the issue without removing the front differential or gas tank prevailed.

Addressing the Vent Pipe: With the vent valve identified, the vent pipe, a critical component in venting air during fueling, came into focus. Navigating through the intricacies of the Carrera 4’s design, we tackled the challenge of accessing the vent pipe while the car was still assembled. This involved feeding the vent pipe back to the top of the gasoline tank, ensuring proper functionality.