MR2 & Previa
- Ensure battery is fully charged. Turn ignition off. Disconnect negative battery cable. On Previa, remove right (engine) service hole cover. On all models, place container or shop towel under fuel delivery pipe.
- Slowly loosen delivery pipe union bolt to relieve fuel pressure. Remove union bolt and 2 gaskets. Install fuel pressure gauge between fuel supply line and delivery pipe. See Fig 1 or Fig 2. Wipe off excess fuel.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Install jumper wire between engine check connector FP and +B pins. See Figure. See ENGINE CHECK CONNECTOR LOCATION table. Connect negative battery cable. Turn ignition on, with engine off. Measure fuel pressure.
- Fuel pressure should be same as unregulated pressure. See FUEL PUMP PERFORMANCE table. If fuel pressure is high, replace fuel pressure regulator. If fuel pressure is low, check fuel hoses and connections, fuel pump, fuel filter and fuel pressure regulator.
- Remove jumper wire installed in step 3). Start engine. Disconnect vacuum sensing hose from fuel pressure regulator, and plug hose end. Fuel pressure regulator is mounted on fuel rail. Measure unregulated fuel pressure at idle speed. See FUEL PUMP PERFORMANCE table.
- With engine idling, connect fuel pressure regulator vacuum hose. Measure regulated pressure at idle. If regulated pressure is not as specified, check vacuum sensing hose to fuel pressure regulator.
- Stop engine. Note fuel pressure. Leave fuel pressure gauge attached to engine for at least 5 minutes. Residual fuel pressure after 5 minutes should be at least 21 psi (1.5 kg/cm2
). If pressure is not as specified, check for leaking injectors, faulty fuel pressure regulator or bad check valve in fuel pump.
- Relieve fuel system pressure. Remove fuel pressure gauge. Install fuel supply line to delivery pipe. Run engine and check for fuel leaks.