Troubleshooting Troubleshooting – Fuel System Estimated reading: 2 minutes Contributors Overview This troubleshooting guide is designed to help diagnose and resolve fuel system issues specific to the 16v engine Porsche 944 S / S2 (1989–1991). Addressing problems like excessive fuel consumption or strong fuel odors in the passenger compartment is critical for maintaining performance, safety, and comfort in your vehicle. The following procedures focus on components relevant to the late-model 944 S / S2, ensuring accurate diagnostics and repairs. Pink and blue text represents links to additional resources, tools, parts, and partner websites. Excessive Fuel Consumption Excessive fuel consumption can result from various fuel system or ignition-related issues. Below is a table of possible causes, checks, and procedures tailored for the 16v S / S2. Possible Causes Checks Procedure Dirty Air Filter Check / Change Air Filter N/A Bad O2 Sensor Check sensor and replace if necessary FUEL-18 Poor Ignition System Function Check the condition of the distributor cap, rotor, spark plugs, and spark plug wires IGN-04 Strong Fuel Smell In Passenger’s Compartment A strong fuel smell inside the vehicle indicates potential leaks or ventilation issues. The following table outlines possible causes, checks, and procedures for the 16v S / S2. Possible Causes Checks Procedure Fuel Level Sender Gasket Locate the fuel level sender and check the condition of the gasket around the sender cap. If it appears hard/brittle, replace the gasket (Part #944-201-327-00). ELECT-13 Fuel Tank Ventilation System Inspect the fuel tank ventilation system hoses running from the tank along the vehicle’s right side, into the engine compartment, along the firewall, to the charcoal canister in the left fender well (remove interior fender well cover to locate). Check for loose, cut, or leaking hoses, or a split charcoal canister. N/A Fuel Filler or Fuel Reservoir System Leak Inspect rubber hoses and sleeves in the fuel filler and reservoir system, located behind the carpet in the rear hatch area and inside the roof pillar on the fuel filler side. Check for holes or loose hose clamps. If a “whooshing” sound occurs when removing the fuel filler cap, the ventilation valve (Part #928-201-083-02) may be stuck. Also, check the fuel cap gasket (Part #944-201-553-00) for leaks. N/A Fuel Filler Neck Distortion Check the fuel filler neck for elongation or distortion, which can prevent the fuel cap from sealing properly (Part #931-201-281-02). N/A Sources Clark’s Garage Pelican Parts Porsche 944 Workshop Manuals YouTube Tagged:Fuel System Troubleshooting Troubleshooting – Fuel System - PreviousTroubleshooting – EngineNext - Troubleshooting – Fuel SystemTroubleshooting – Heating, Ventilation, and Air Conditioning (HVAC)
