Repair And Fix it

Ford F-150 fuel injectors are designed for long life. While regular cleaning will keep the fuel injectors performing well, fuel injectors have moving parts that wear out. Worn or broken fuel injectors result in inadequate or too much fuel being consumed during the combustion process. Incorrect fuel combustion may result in damage to the engine or catalytic converter. Fuel injectors which are worn or damaged should be replaced. To avoid future failures, if one fuel injector has gone bad due to wear and tear, replacement of all the injectors is recommended.

Instructions

Access the Fuel Injectors

1

Depressurize the fuel system. If your vehicle is equipped with a fuel safety cut-off switch--usually located on the passenger side front foot panel on the F-150--access and remove the electronic plug. This will disable the fuel pump. Turn on the engine several times to remove any fuel pressure in the lines. The engine will not stay started, this is normal.

2

Disconnect the battery cables to avoid fire hazards when working with fuel.

3

Remove any engine shroud, air intake tube, vacuum lines and other bolt-on accessories that restrict access to the fuel rails. Unbolt the fuel rail from the engine. The metal fuel rail will be braced to the engine with one or two bolts.

4

Remove the fuel injector electronics plug from each injector to be replaced.

5

Lift the fuel rails off the fuel injectors. Lift the end of the fuel rail closest to the bumper and pop each fuel injector free. Some injectors will stay in the engine and others will remain in the fuel rail. All injectors that are freed from either the engine or fuel rail will need new o-rings.

6

Remove the fuel injector from both the engine and the fuel rail. Inspect the injector for missing o-rings. Two o-rings should exist, one for the top connection on the fuel rail, and one for the bottom connection to the engine. Locate the missing o-rings and discard.

Replace the Injectors

7

Replace the o-rings with new o-rings. Lubricate the new o-rings with motor oil and slide over the ends of the fuel injectors. New injectors commonly come with o-rings installed. Lubricate the pre-installed o-rings with motor oil. A drop of oil on your finger smeared on the o-ring is sufficient.

8

Insert the new fuel injector into the engine hole. Press downward until the fuel injector is seated properly. A popping sensation may be felt, but not always. Pull upward on the injector. A properly seated injector will resist removal.

9

Replace all o-rings on the injectors from which the fuel rail was removed. Replace the fuel rail on each injector.

10

Bolt the fuel rail to the engine and replace any bolt-on accessories removed to access the fuel rail. Replace the fuel injector electronics plugs. Replace any vacuum lines removed. Replace the air intake tube. Replace the engine shroud, if equipped.

11

Reconnect the battery. Reconnect the fuel safety cut-off switch plug. Turn the ignition key to the electronics only mode for five seconds and turn off. Repeat the ignition key on/off sequence twice to allow the fuel pump to pressurize the fuel line. Inspect the fuel rails for leaks and repair. If necessary, return to step 1.

12

Start the vehicle to confirm installation.

The most recent use of a 4.9-liter engine in Ford vehicle is in F-150 pickup trucks made from 1987 to 1996. This is a six cylinder gasoline engine, which requires the fuel injectors to deliver fuel to the engine under high pressure. The installation of a new fuel injector for a 4.9-liter Ford engine requires you to remove the entire fuel rail assembly. This procedure is generally the same for all Ford trucks with a 4.9-liter engine made since 1987.

Instructions

1

Disconnect the cable on the negative battery terminal with a socket wrench to reduce the possibility of a spark while replacing the fuel injectors. Open the filler cap on the fuel tank to relieve the pressure in the tank. Remove the cap for the fuel pressure relief valve on the fuel line and connect MFI Pressure Gauge T80L-9974-A to the valve. Open the pressure gauge to relieve the pressure in the fuel lines and replace the valve cap.

2

Disconnect the upper intake manifold assembly from the engine with a socket wrench. Remove the mounting bolts for the fuel rail and disconnect the fuel rail from the engine. Unplug the electrical connector for each fuel injector.

3

Rock the fuel injector back and forth as you pull up to remove the fuel injector from the fuel rail. Remove and discard any damaged O-rings from the fuel injector.

4

Coat the new O-rings with clean engine oil and mount them to the new fuel injector. Install the new fuel injector into the fuel rail by gently rocking it back and forth.

5

Attach the electrical connectors for the fuel injectors, and install the fuel rail with the socket wrench. Replace the upper intake manifold and connect the cable to the negative battery terminal.

N14 is the internal designator for the fourth generation of the Nissan Pulsar, which was manufactured from 1990 to 1995. It was also sold under several other names, including the Sentra in New Zealand and the Sunny in Europe. The N14 was available with a variety of four-cylinder engines, ranging in size from 1.3 liters to 2.0 liters. The procedure for installing a fuel injector is generally the same for all N14 vehicles.

Instructions

1

Remove the fuse for the fuel pump located in the fuse block of the engine compartment. Start the vehicle and allow it to stall. Crank the engine for at least three seconds to ensure the fuel system is empty. Replace the fuel pump fuse.

2

Disconnect the cover for the fuel injector with a socket wrench. Note the alignment of the injector terminals and lift the fuel injector straight out of the injector bore. Ensure that you do not bend the electrical terminal on the injector. Discard the old O-rings for the fuel injector.

3

Mount a new lower O-ring onto the fuel injector. Install the injector into the bore by pressing down firmly without damaging the electrical terminal. Rotate the injector within the bore to align its electrical terminal as noted in step two. Mount a new upper O-ring onto the fuel injector.

4

Remove the rubber plug from the cover of the fuel injector. Mount both of the O-rings for the fuel injector cover, and install the cover with a socket wrench. Ensure that the electrical terminal for the fuel injector connects properly with the terminal on the injector cover. Replace the rubber plug on the fuel injector cover.

5

Start the engine and check for leaks in the fuel system.

The fuel injectors for an Audi A6 deliver fuel to the engines cylinders in a specific sequence, allowing the vehicle to to be more responsive than its carburetted counterparts. The procedure for changing the fuel injectors is generally the same for all A6s.

Instructions

1

Turn off the ignition. Remove the fuse for the fuel pump, using the list on the fuse box as a guide. Start the engine and allow it to idle until it stalls. Turn the ignition off and disconnect the negative battery cable with a socket wrench. Replace the fuel pump fuse.

2

Wrap a clean shop rag around one of the fuel-line connections to the fuel rail. Loosen the retaining nuts for the fuel line with a socket wrench to relieve the pressure in the fuel tank. Properly dispose of the rag.

3

Remove the retaining nuts for the fuel lines, and detach the fuel lines from the fuel rail. Disconnect the mounting bolts for the fuel rail with a socket wrench, and remove the fuel rail from the intake manifold with the injectors still attached. Turn the fuel injectors counterclockwise to remove them from the fuel rail.

4

Mount a new lower gasket to the nozzle end of the fuel injectors. Clean the threads of the fuel injectors with a clean shop rag, and apply a thin layer of thread-lock compound to the threads. Screw the fuel injectors clockwise with a socket wrench to install them into the fuel rail, and mount a new upper gasket to the open end of the fuel injectors.

5

Mount the fuel rail to the intake manifold, and fasten the mounting bolts with a socket wrench. Connect the fuel lines to the fuel rail, and fasten the retaining nuts for the fuel lines. Reattach the cable for the negative battery terminal.

The Ford F-Series is a line of full-size pickup trucks in continuous production since 1948. The F150 models have a nominal carrying capacity of at least 1/2 ton, although the actual payload is typically more than 1/2 ton. A 1989 Ford F150 has a variety of engine choices and all of them come with fuel injection. The procedure for installing a fuel injector in this vehicle will vary slightly depending on the size of the engine.

Instructions

1

Disconnect the cable on the negative terminal of the battery with a socket wrench. Loosen the cap on the fuel tank to relieve the pressure in the fuel tank. Remove the valve cap from the fuel pressure relief valve on the fuel line in the upper right quadrant of the engine compartment.

2

Attach pressure gauge T80L-9974-A to the relief valve and open the pressure gauge to relieve the pressure in the fuel system. Remove the pressure gauge from the relief valve and place the cap on the relief valve.

3

Disconnect the upper intake manifold with a socket wrench. Remove the fuel rail and detach the electrical connection for each fuel injector.

4

Remove the fuel injectors from the lower intake manifold by rocking the fuel injectors gently back and forth while pulling up. Replace any worn O-rings or plastic caps for the fuel injectors.

5

Apply engine oil to the O-rings and put them on the new fuel injectors. Place the plastic caps onto the top of the fuel injectors. Install the fuel injectors onto the lower intake manifold by pushing them in gently as you rock them back an forth.

6

Attach the electrical wiring to the fuel injection and install the fuel rail. Connect the upper intake manifold if you removed it in Step 3. Connect the cable to the negative battery terminal with a socket wrench.

Fuel injectors operate in conjunction with a high pressure fuel system. The fuel injector head is connected to the fuel line and engine through a O-ring seal. The O-ring allows the injector to be seated, in both the fuel line and engine, without requiring bolts, screws or threaded connectors. Injector leaks stemming from poor O-ring connections may be caused by O-ring shrinkage, exposure to high heat, chemical decomposition, or tears in the O-ring material. Leaks coming directly from the injector require full injector replacement. Replace O-rings whenever an injector is removed from the fuel line or engine, for best results.

Instructions

1

Pressurize the fuel system by turning the ignition key to the "electronics only" mode. The fuel pump will turn on pressurize the fuel lines. If in doubt, turn on the vehicle briefly.

2

Lift the hood. Inspect the fuel injectors and connections for leaks. If fuel is leaking from the injector seal at the fuel line -- the point at which the injector connects to the fuel rail -- the leak is most likely due to O-ring failure. If the fuel is leaking directly from the injector, the injector needs to be replaced. Fuel leaks inside the engines cylinders, often reported by the on-board computer as lean or rich conditions, will require injector replacement.

3

Depressurize the fuel system. Remove the plug to the fuel safety cut-off switch, if equipped, to disable the fuel pump. Fuel safety cut-off switch locations can be found in the vehicles owners manual. Attempt to start the vehicle several times to use any remaining fuel. Remove the ignition key and disconnect the battery.

Injector Removal

4

Remove any vehicle components restricting access to the fuel line. Air intakes, electronics, vacuum hoses and components should all be carefully labeled to ensure they are correctly reinstalled when you are finished servicing the vehicle. Disconnect the fuel injector plug.

5

Disconnect the fuel rail from the fuel injector. Some fuel rails are bolted to the engine. Remove any bolts which prevent removal of the fuel rail. Pull the rail directly away from the fuel injector to disengage the seal. A small amount of fuel may spill from the rail, once the rail is lifted from the injector. Wipe up any fuel before continuing.

6

Grasp the injector with your hands, to avoid tool damage to the injector, and pull directly away from the engine to remove the injector. Rock the injector if the seal is tight. You may feel a slight popping sensation when the injector releases.

7

Inspect the fuel injector for physical damage. Cracked or damaged injectors should be replaced.

8

Remove the O-rings from the top and bottom of the injector. Clean the injector head and nozzle with a brake parts cleaner saturated cloth and allow to dry.

Leak Fixing

9

Install new O-rings on the removed injectors. Coat the O-rings with a small amount of motor oil. The motor oil will lubricate the O-rings during installation to help prevent small tears during the seating process and help prevent the breakdown of the O-ring during use. Slide an O-ring over each end of the injector until the O-ring is seated in the gap provided for the seal.

10

Grasp the injector with your hand and push the injector into the injector hole on the engine. You may feel a small pop as the injector becomes seated. When correctly installed, the injector will resist removal.

11

Press the fuel line onto the injector head, until it is firmly seated.

12

Reconnect the fuel injector plug. Reattach the fuel rail to the engine, if required. Connect any engine components initially removed to provide access to the fuel injectors. Connect the battery.

13

Reconnect the fuel safety cut-off switch, if disabled. Turn on the vehicle for 15 seconds to allow the fuel lines to pressurize. Check for leaks. Start the vehicle to confirm installation.

A cleaning job on a vehicles fuel injector heads only takes a little more than 10 minutes to complete. However, this cleaning could make a world of difference, as dirty injector heads can adversely affect the performance of an automobile.

Significance

Its important for injector heads to be cleaned because of the effects they can have on an automobiles engine if left unchecked. Vehicles may hesitate during takeoff or not perform with the same power as they normally would. Even a partially clogged injector can lead to engine misfiring problems.

Deposits

Injector heads need to be cleaned because as time passes deposits can accumulate on them, leaving them clogged. Deposits are a result of compounds within the engines fuel that get baked onto the injector heads when the engine is off but still hot. Without fuel flowing through the injector, nothing stands in the way of this slow deposit build up.

Time Frame

Fuel injector heads will have a greater need for cleaning on vehicles that have traveled longer distances. Although these distances can vary, experts warn that cleaning should be performed on fuel injectors after about 27,000 miles have been driven.

The Chevrolet Blazer was a mid-size sport utility vehicle made by General Motors from 1983 to 2005. The second generation of this model was in production from 1995 to 2005 and all of these vehicles were equipped with a six-cylinder 4.3-liter engine. Each cylinder of an engine has its own fuel injector, which delivers fuel and air in a precise sequence. You can replace an individual fuel injector on the 1997 Chevrolet Blazer.

Instructions

1

Remove the air cleaner with a socket wrench and disconnect the cable on the negative battery terminal. Open the filler cap for the fuel tank to relieve the pressure in the fuel tank.

2

Press the two tabs on the fuel injectors electrical connector together, and pull the electrical connector up to disconnect it from the fuel injector. Remove the cover for the fuel meter with a socket wrench and discard its gasket. Lift the fuel injector from the fuel meter carefully with a small pry bar.

3

Remove the small O-ring from the nozzle of the fuel injector. Detach the fuel filter from the fuel injector by carefully rotating the fuel filter back and forth. Remove the large O-ring and washer from the injector cavity of the fuel meter.

4

Apply a thin layer of transmission fluid to the small O-ring and push it onto the nozzle of the injector until it is flush against the fuel filter for the injector. Install the washer into the cavity of the fuel meter and apply transmission fluid to the large O-ring. Seat the large O-ring against the washer so that it is flush with the top of the fuel meter.

5

Align the raised lug on the base of the fuel injector with the notch in the cavity of the fuel meter. Press the fuel injector down firmly to ensure that it is fully seated. Install the cover for the fuel meter and its new gasket. Attach the electrical connector to the fuel injector. Start the engine and check for fuel leaks.

The 300ZX is a sports car that Nissan sold in the United States from 1984 to 1996. The 1984 models had 2.0-liter and 3.0-liter engines, and some units also had turbochargers. All versions of the 1984 300ZX have fuel injection, which delivers fuel and air to the engine in a precise ratio. The fuel injector assembly in a 1984 Nissan 300ZX is accessible from the engine compartment and is located on top of the engine.

Instructions

1

Start the engine and remove the fuse for the fuel pump in the fuse box. Allow the engine to stall and crank the engine to ensure that it will not start. Turn the ignition off once you have removed all of the fuel from the fuel system. Replace the fuse for the fuel pump.

2

Detach the electrical connector from the fuel injector, and disconnect the wiring harness from the wiring clamp on the fuel pipe. Remove the hose from the cover on the rocker arm. Disconnect the vacuum hose from the pressure regulator and detach the pipe to the air regulator.

3

Place a shop towel under the fuel pipe to catch spilled fuel. Disconnect the fuel feed line and fuel return line from the fuel pipe.

4

Remove the bolts for the fuel pipe and the retaining screws for the fuel injector with a socket wrench. Detach the entire fuel injector assembly from the engine, including the fuel injectors, fuel pipe and pressure regulator. Release the clamps for the hose on the fuel pipe and separate the fuel pipe from the fuel injector.

5

Inspect the new insulator washers for the fuel injector to ensure they have no abrasions. Install the new insulator washers to the new fuel injector so they form an airtight seal. Install the new fuel injectors by reversing steps two through four. Start the engine and check for fuel leaks.

To get the best performance from a vehicles engine, its a must for fuel injectors to be clean. Dirty injectors can not effectively provide an engine with fuel the way clean injectors can. Because of this, information on testing and cleaning fuel injectors can be valuable to vehicle owners.

Clogging

A restriction of as little as 9 percent in one fuel injector is enough to cause an engine to misfire. However, the fuel deposits that clog injectors tend to happen more in older vehicles that have pintle-style injectors. Many newer model vehicles have fuel injectors that are designed to prevent such easy clogging.

Testing

Fuel injectors can be checked through a process called flow-testing. The flow rate of an injector is tested, and reveals if the injector fails to meet factory standards. Injectors are removed from the vehicle when performing a flow test.

Cleaning

Fuel injector cleaning can be accomplished by adding injector cleaner into the gas tank of your vehicle. You may also have a professional shop remove your injectors for cleaning. Either way, it is recommended to have fuel injectors cleaned about every 27,000 miles.