Fuel Volume & Pressure: Notes

Begin basic fuel system diagnosis by determining fuel system pressure.

1. Remove engine cover to gain access to fuel lines. Prepare Pressure Testing Kit (135220) which consists of Check Valve (135221) and Adapter (135222). Remove dust cap from measuring valve on fuel rail. Connect check valve and gauge to fuel rail. Block (plug) fuel return line with Fuel Hose Clamp (133010).
2. Remove fuel pump relay. See DME & FUEL PUMP RELAY LOCATION  table. Using Fuel Pump Relay Bridging Caliper (613050) or jumper wire, connect terminals No. 87 and 30 at fuel pump relay socket. See Figure. This will turn fuel pump on.
3. Disconnect fuel return line. Install extension hose and hold end of hose in Graduated Glass Container (133020). Check fuel pump delivery rate. See FUEL PUMP PERFORMANCE  table.
   FUEL PUMP PERFORMANCE
   
   

   Application	Pressure psi (kg/cm2 )	Min. Vol. In 30 Sec. Pts. (L)
   6-Cylinder & V8	50 (3.5)	1.85 (0.9)
   V12	50 (3.5)	2.3 (1.1)