Filed Under (Honda) by admin on 11-12-2010
FUEL SYSTEM PRESSURE RELEASE NOTE: 1. Loosen fuel tank filler cap to relieve tank pressure. Remove fuel pump relay from underhood fuse/relay box. Start and operate engine until it stalls. Crank engine an additional 30 seconds. 2. Loosen hose clamp of fuel line on side of pressure regulator, coming from fuel line inlet distributor pipe. Cover fuel hose with a shop towel, and slowly pull hose from pressure regulator to relieve fuel pressure. When fuel stops leaking, reinstall hose and clamp. FUEL PRESSURE & FUEL PUMP RELAY TEST NOTE: Fuel Pressure 1. Relieve fuel pressure. See FUEL SYSTEM PRESSURE RELEASE . Attach Fuel Pressure Gauge Set (J-34730-1 ) and Adapter (J-35957-1 ) to Schrader fitting on fuel rail. Disconnect pressure regulator vacuum hose. Turn ignition on. Allow fuel pump to run for about 2 seconds. 2. Fuel system pressure should be about 41-46 psi (2.8-3.2 kg/cm2 ). See FUEL PUMP PERFORMANCE . Start engine and check for leaks. Connect pressure regulator vacuum hose. If engine will not start, the fuel pump relay can be by-passed. Also see appropriate CHART A-3 – ENGINE CRANKS BUT WILL NOT RUN under TROUBLE SHOOTING CHARTS. With engine idling, fuel pressure should be 25-30 psi (1.8-2.1 kg/cm2 ). NOTE: Fuel pump relay is located in engine compartment fuse/relay box. Begin basic fuel system diagnosis with testing fuel pressure. To test the fuel pump relay circuit, proceed to CHART A-5 – FUEL PUMP RELAY CIRCUIT under TROUBLE SHOOTING CHARTS. Fuel Pump Relay 1. ECM supplies power to relay as long as ECM receives ignition reference signals or starter crank signal. To run fuel pump without starting engine, remove relay and jumper terminals No. 2 and 4. See Fig. 5 and Fig. 6 . 2. To test relay, use jumper wires to ground terminal No. 4 of relay and apply battery voltage to terminal No. 2 of relay. Using ohmmeter, check for continuity between relay terminals No. 1 and 3. If continuity is not present, replace relay.
Filed Under (Ford) by admin on 15-02-2011
Removal 1. Remove fuel tank (9002) as described. 2. Remove any dirt that has accumulated around fuel pump module retaining flange. 3. Turn fuel pump module locking retainer ring counterclockwise using Fuel Tank Sender Wrench 310-002 (T74P-9275-A) and remove fuel pump module locking retainer ring. 4. Pull fuel pump module sender plate up out of fuel tank until locking tabs for fuel pump module are accessible. Reach through fuel pump module opening, squeeze both locking tabs together and remove fuel pump module from fuel tank . 5. Remove O-ring seal and discard. Installation 1. Clean fuel pump module retaining flange, fuel tank mounting surface and seal ring groove. 2. Apply a light coating of Premium Long-Life Grease XG-1-C or equivalent meeting Ford specification ESA-M1C75-BA on a new O-ring seal to hold it in place during assembly and install O-ring in seal ring groove. 3. Install fuel pump module carefully into fuel tank to make sure that filter, hoses and float rod are not damaged or binding. Align fuel pump module and fuel tank retainer and push fuel pump module into fuel tank retainer. A definite click will be heard when the two tabs on fuel pump module engage the fuel tank retainer. The fuel pump module must be snapped in the retainer with both tabs. Pull on fuel pump module to make sure it is fully engaged. Install fuel pump module sender plate to fuel tank , being careful that locating keys are in keyways and O-ring seal remains in place. 4. Hold assembly in place and install fuel pump module locking retainer ring finger-tight. Make sure that all locking tabs are under fuel pump module locking retainer ring tabs. 5. Secure fuel pump module unit by rotating fuel pump module locking retainer ring clockwise using Fuel Tank Sender Wrench 310-002 (T74P-9275-A) until fuel pump module locking retainer ring contacts the stops. 6. Install fuel tank in vehicle as described. 7. Lower vehicle. 8. Install a minimum of 38 liters (10 gallons) of fuel. Check for leaks. 9. Turn ignition switch to RUN position for three seconds repeatedly (5 to 10 times) until Multiport Fuel Injection (MFI) Fuel Pressure Gauge 310-012 (T80L-9974-B) or equivalent (depending upon application) shows at least 207 kPa (30 psi). Check for leaks at fittings. 10. Remove Multiport Fuel Injection (MFI) Fuel Pressure Gauge 310-012 (T80L-9974-B) or equivalent (depending upon application), start engine and recheck for leaks.
Filed Under (Ford) by admin on 25-03-2011
Fuel Charging and Controls The fuel charging and controls system consists of: fuel pressure regulator (9C968) fuel injection supply manifold (9F792) fuel injectors (9F593) fuel shut off valve solenoid (9D278) fuel pressure relief valve (9H321) injection pressure sensor engine fuel temperature sensor fuel charging wiring harness Component Location Fuel Pressure Regulator The fuel pressure regulator is located on the inside of the LH frame rail just forward of the transmission support crossmember. It is part of an assembly that includes the coalescer/filter. The fuel pressure regulator reduces the line pressure from tank pressure 20685 kPa (3000 psi) to line pressure 655 kPa (95 psi). Heating/Defrosting—Natural Gas Vehicle Fuel pressure regulator heating is provided by two 3/8-inch taps from the existing heater supply and return hoses on the RH rear of the engine. Two high-temperature 3/8-inch ID heater hoses (packaged with the front low-pressure fuel line) are used to connect the fuel pressure regulator to the tap points on the engine heater hoses. Refer to the Line — Low Pressure Fuel procedure in Section 310-01B for fuel pressure regulator heater hose replacement. Fuel Pressure Regulator Heater Hoses Fuel Injection Supply Manifold The fuel injection supply manifold delivers high-pressure fuel from the vehicle fuel supply line to the fuel injectors. The fuel injection supply manifold consists of the following: a tubular fuel rail eight fuel injector connectors a fuel pressure relief valve a fuel shut off valve solenoid mounting attachments which locate the fuel injection supply manifold and provide fuel injector retention. a fuel inlet connection which has a push-connect fitting an injection pressure sensor an engine fuel temperature sensor Fuel Injection Supply Manifold Fuel Injectors The natural gas fuel injectors are electro-mechanical devices that meter fuel delivered to the engine. The natural gas fuel injectors are mounted in the lower intake manifold (9424) and are positioned so that their tips direct fuel just ahead of the engine intake valves (6507). The natural gas fuel injector bodies consist of a solenoid and a needle and valve assembly. Natural gas fuel injectors can be identified by an aqua cap on the injector body. Fuel Shutoff Valve Solenoid The fuel shut off valve solenoid seals the upstream fuel pressure from entering the fuel injection supply manifold when the engine is not running. The fuel shut off valve solenoid is open only when it is activated by the solenoid valve (fuel pump) relay. Fuel Pressure Relief Valve The fuel pressure relief valve is located on the fuel injection supply manifold, and is used to relieve fuel system pressure from the fuel delivery system. Injection Pressure Sensor The injection pressure sensor is located on the fuel injection supply manifold, and is used to provide a signal to the powertrain control module (PCM) (12A650) that is proportional to pressure in the fuel injection supply manifold. Engine Fuel Temperature Sensor The engine fuel temperature sensor is located on the fuel injection supply manifold, and is used to provide a signal to the powertrain control module that indicates the temperature of the fuel in the fuel injection supply manifold. Fuel Charging Wiring The fuel charging wiring is a single harness that includes electrical connectors for the fuel injectors, ignition coils and various sensors, valves and senders that monitor all engine functions. Fuel Charging Wiring
Filed Under (Dodge) by admin on 07-12-2010
1. Remove fuel pump relay from power distribution center at driver’s side front corner of engine compartment, near the battery. Note terminal identification on fuel pump relay. See Fig. 6 . 2. To check fuel pump relay resistance, use ohmmeter and check resistance between terminals No. 85 and 86 on fuel pump relay. Replace fuel pump relay if resistance is not 70-80 ohms. 3. To check fuel pump relay operation, connect ohmmeter between terminals No. 30 and 87A on fuel pump relay. See Fig. 6 . Ohmmeter should indicate continuity between terminals No. 30 and 87A on fuel pump relay. 4. Connect ohmmeter between terminals No. 30 and 87 on fuel pump relay. See Fig. 6 . Ohmmeter should indicate no continuity between terminals No. 30 and 87 on fuel pump relay. CAUTION: DO NOT allow ohmmeter leads to contact terminals No. 85 and 86 on fuel pump relay when fuel pump relay is energized. 5. Connect 16-gauge jumper wire between negative battery terminal and terminal No. 85 on fuel pump relay. Connect 16-gauge jumper wire between positive battery terminal and terminal No. 86 on fuel pump relay. 6. Fuel pump relay should now be energized. No continuity should now exist between terminals No. 30 and 87A on fuel pump relay. Continuity should now exist between terminals No. 30 and 87 on fuel pump relay. Disconnect jumper wires. Replace fuel pump relay if defective. 7. If fuel pump relay or wiring circuit failure exists, a Diagnostic Trouble Code (DTC) will be stored in Powertrain Control Module (PCM). See appropriate G – TESTS W/CODES article.
Filed Under (Isuzu) by admin on 23-12-2010
NOTE: 1. Release fuel pressure. See FUEL SYSTEM PRESSURE RELEASE . Install a fuel pressure gauge between fuel pressure regulator and fuel distributor pipe. See Fig. 1 . Bleed air from fuel line going to pressure gauge. 2. Unplug fuel pressure regulator Vacuum Switching Valve (VSV) connector on right side fender skirt. This is a 4-wire connector with Black and Blue wires in harness. PCM controls VSV to cut vacuum to fuel pressure regulator during hot engine starts. 3. Start engine and measure fuel pressure at idle. Disconnect fuel pressure regulator vacuum hose. Note fuel pressure at idle with vacuum hose disconnected (no vacuum). Fuel pressure should be 42 psi (3.0 kg/cm2 ). See FUEL PUMP PERFORMANCE . 4. If fuel pump pressure is low, check for fuel leaks, restrictions in intake side of fuel pump, leaking injectors, faulty pressure regulator or faulty fuel pump. If fuel pressure is high, check for restrictions in return line to tank or faulty pressure regulator. If pressure does not change when pressure regulator is disconnected, replace pressure regulator. 5. Reconnect pressure regulator vacuum hose and check fuel pressure (with vacuum). Fuel pressure should be 35 psi (2.4 kg/cm2 ). Apply battery voltage to VSV connector Blue wire terminal, and ground Black wire terminal (with vacuum). See Fig. 2 . Fuel pressure gauge should read about 42 psi (3.0 kg/cm2 ). If fuel pressure is not within specification, check for defective VSV. 6. Disconnect and plug vacuum hose from fuel pressure regulator. Stop engine and ensure fuel pressure remains greater than 35 psi (2.4 kg/cm2 ) for 4 minutes after engine stops. 7. If pressure drops, check for leaking injectors, faulty pressure regulator or bad check valve in fuel pump. If engine does not start, by-pass fuel pump relay to check for fuel pressure. Remove fuel pump relay from underhood fuse/relay box. Connect a fused jumper wire between terminals No. 1 and 3 of fuel pump relay connector in fuse block. See Fig. 3 and Fig. 4 . 8. If fuel pump does not operate, check for battery voltage to terminal No. 3. If battery voltage is present, check for open in fuel pump circuit. If fuel pump operates with jumper wire installed, check fuel pump relay and relay energizing circuit. Repair as necessary. Begin basic fuel system diagnosis with testing fuel pressure.