Fuel Line Pressure Under Load
- Install Fuel Pressure Gauge (49 UN01 010) to fuel pressure relief valve (Schrader valve) located on fuel rail. Disconnect and plug fuel pressure regulator vacuum hose. Start engine and drive vehicle under heavy acceleration. Verify fuel line pressure does not increase or decrease more than 3 psi (.21 kg/cm2 ) during heavy acceleration.
- If fuel pressure is not as specified, remove fuel vapor valve from top of fuel tank. Blow air through fuel vapor valve port with valve port upright. Air should flow through bottom of valve. Turn fuel vapor valve upside down and blow air through valve port (port should be on bottom). Air should not flow through valve.
- If air does not flow as specified, replace fuel vapor valve. If air flows as specified, replace fuel filter.