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Replaced the column now no power to the fuel pump in run position. also replaced computer to the one matching the column

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Make sure fuel pump is getting power. Im not sure but I think ignition is wired through fuel pump so if it dont pump fuel it wont spark either

Feb 22, 2013 | 1999 GMC Jimmy

1 Answer

I have a 88 F250.....Fuel Pump runs constantly...even with key off. Replacing pump did not help. Also have a problem with steering column. It will not engage the starter switch. Something keeps draining...

Locate the fuel pump relay by looking at the inside of the fuse box cover or the owners manual. Remove the relay and see if the pump stops. If it does, then locate another relay in the same fuse box that has the same part number on it and is not required for engine operation like a wiper motor or AC control relay. Install that relay in place of the fuel pump relay and see if the pump continues to run. If it doesn't then start the engine to verify proper operation. If it runs OK, then shut it off and check to see if the pump is still running. If it's not still running then replace the fuel pump relay. If it still continues to run then the most likely cause is a shorted wiring harness. The harness usually runs along the floor board and can short out by making contact with the vehicle body. As for the steering column, try this if the gear selector is on the column. Grasp the selector lever and pull up on it while trying to start the vehicle. If the vehicle now starts then column linkage is worn, a common problem with ford column shifters.

May 17, 2011 | 1988 Ford F 250

3 Answers

Fuel pump not getting power.Replaced fuel relay and pump. computer code was reading cam position sensor. I dont believe that would cause a no power to fuel pump. It is trying to turn and it will turn with...

If it is similar to Quest, the fuel pump runs for 5 seconds when you turn the key to ON. Then, unless the engine is running, the pump shuts off. It runs when the key is in START position though. Can you hear the pump run for 5 seconds when you turn key to ON? Listen carefully for the hum of the pump in the tank.
Normally, the power relay powers up the PCM and it applies power to the fuel pump relay. Then you get power to the pump.
Also, look at owner manual for all fuses that apply to fuel pump system.

Jan 05, 2011 | 1998 Nissan Pathfinder

1 Answer

Car cranks but dose not start, there is no power to distributator or fuel pump

I suspect the at this point, the main relay is defective. This relay controls power to fuel and spark circuits.

The PGM-FI Main Relay is actually comprised of two individual internal relays. When the ignition switch is initially turned ON , the Powertrain Control Module (PCM) supplies ground to the PGM-FI Main Relay. This ground triggers one of the PGM-FI internal relays that sends battery voltage to the fuel pump for two seconds to pressurize the fuel system.
When the engine is running the PCM supplies a continuous ground to the PGM-FI Main Relay. The supplied ground keeps the relay in the "closed" position providing electrical current to the fuel pump, keeping the fuel loop pressurized while the engine runs.
If the engine is not running with the ignition on, the PCM cuts the ground to the PGM-FI Main Relay, causing the relay to "open" and stop the electric current flow to the fuel pump. As mentioned previously, if the engine is not running, the PCM will only supply ground to the PGM-FI Main Relay for two seconds when the ignition switch is initially switched to the ON position.
The PGM-FI Main Relay also supplies electrical power to the Idle Air Control (IAC) Valve and to the fuel injectors.


If the engine starts and continues to run, the PGM-FI Main Relay is working and does not need to be replaced.
  1. Locate and remove the relay.

On some models of the Civic and Civic del Sol it is located to the left of the steering column under the dash. Many later models position it either near the passenger right side kick panel under the dash or by the driver left side kick panel up under the dash.
  1. Attach the battery positive terminal to the No. 2 terminal.
  2. And the battery negative terminal to the No. 1 terminal.
  3. Check for continuity between terminal No. 5 and 4.
  4. If there is no continuity, replace the relay and retest

Aug 05, 2010 | Honda Civic Cars & Trucks

1 Answer

I have a 1994 oldsmobile 88 Royale with a 3.8 v6. I have asked this question to 2 "experts" and no one seems to be willing to answer this question: There is linkage that goes from the lock cylinder down...

The starter switch fails commonly. If the linkage does not move then it has probably broken loose from the ignition switch and switch will have to be replaced.
  • Disconnect battery ground cable . Remove the upper steering column shroud by removing the self-tapping screws. Remove four bolts retaining lower steering column shroud and remove lower steering column shroud.
  • Remove lock screw and disconnect the ignition switch electrical connector.
  • Rotate the ignition switch lock cylinder to the RUN position.
  • Remove the two screws retaining ignition switch .
  • Disengage the ignition switch from the actuator.

  • NOTE: A new replacement ignition switch assembly will be set in the RUN position as received.

    Jun 19, 2010 | Cars & Trucks

    2 Answers

    1998 chevy blazer running really rough. It used

    I had a similar problem and just happened to unplug the temperature sensor for the computer and the engine started running smooth.
    So I replaced the temperature sensor and all was well!

    Apr 27, 2010 | 1998 Chevrolet Blazer

    1 Answer

    Fuel pump replacement

    How to Replace a Fuel Pump

    1. Fuel Pump - $51.16


    DELPHI, ELECTRIC FUEL PUMP -- Meets Or Exceeds OEM Quality, Matches The Genuine Fit And Function

    1. 3/8 in. Drive Ratchet
    2. Floor Jack
    3. Multimeter
    4. Jack Stand Set
    5. Flat Head Screwdriver
    6. Mallet Hammer
    7. Socket Set

    Step 1 * Locate the fuel pump.
    o Tip: Safety Tip:Always wear safety glasses when working on your vehicle. Wear other personal protective equipment (PPE) when necessary, for example latex gloves or safety shoes.

    Step 2 * Have a friend turn the key to the“ON” position while you listen for a high pitched hiss/whine coming from the electric fuel pump.
    o Tip: If the fuel pump is located in the fuel tank, you can open the fuel cap and listen to hear the fuel pump. The fuel pump should run (priming the system with fuel) for a couple of seconds. Once it stops, you should be able to start the vehicle.

    Step 3 * If the fuel pump does not make a sound (run and prime the fuel system) check to see if there is a fuse that supplies power to the fuel pump and check its location.
    o Tip: Check the owner’s manual for location of the fuse box and fuel pump fuse.

    Step 4 * Once you have found the location of the fuel pump fuse, remove the fuse from its housing and check to see if it is blown.
    o Tip: A blown fuse will usually have a metal strip connecting both tabs that“blows out” (the wire looks as if it has been chopped in half or broken).

    Step 5 * If you noticed that the fuse was blown, replace the fuse with a new fuse of the same amperage and repeat step 2.

    Step 6 * If the fuel pump now works, you do not need to replace it. However, you will need to find what caused the fuel pump fuse to blow. We strongly recommend that this is done through a certified shop, unless you have the tools and knowledge to test electrical systems and diagnose more in depth problems.

    Step 7 * If the fuse wasn’t blown, it should be checked for power and ground at the fuel pump. If there is power and ground present then you will need to replace the fuel pump.
    o Tip: On most vehicles you may need to lower the fuel tank to access the power and ground leads for the fuel pump.

    Step 8 * Siphon or drain as much fuel as possible from the fuel tank. Disconnect any possible fuel lines from the fuel tank.

    Step 9 * Remove any retaining straps or bolts holding the fuel tank to the frame.
    o Tip: You may be able to access the fuel pump from the bottom of the back seat or the trunk of the vehicle.

    Step 10 * Using a digital multi meter, turn the key to the“ON” position and check for power at the fuel pump. Touch the negative lead from the DMM to a good ground and the positive lead of the DMM to the power cable at the fuel pump. You should have a reading that is equal to battery power. If you do not have a reading at all, you will need to inspect the power side of the fuel pump.
    o Tip: With the ground lead of the DMM still connected to a good ground, touch the power lead to the positive side of the battery, to each side of the fuse, and again to the fuel pump. Wherever you notice the voltage reading goes from battery voltage to 0 you will need to replace whatever wires and fuse are in between.

    Step 11 * If you have noticed that the power and ground being supplied to the fuel pump are both good, then you will need to replace the fuel pump.
    o Tip: To check for a good ground, place the negative lead from the DMM to the ground side of the fuel pump, and the positive lead of the DMM to the positive side of the battery. If the reading on the DMM is battery voltage then you have a good ground.

    Step 12 * Remove any retaining rings or bolts that hold the fuel pump in the fuel tank.

    Step 13 * Remove any electrical connections or fuel lines connected to the fuel pump. Replace the fuel pump.
    o Tip: If equipped, inspect and replace strainer as needed.

    Step 14 * Use reverse procedure to install fuel pump and assemble all components back to their original state.

    Step 15 * Start the vehicle to verify repairs.

    Good job (remember rated and comment this help).

    Mar 03, 2010 | 1997 Nissan Pathfinder

    1 Answer

    No power to the fuel pump. looking for a wiring diagram.

    The 15a efi fuse pwoers the computer fuel system components including the pump. If you NEVER have pump power, I would check the FP terminal in the underhood diag connector...this is the FUEL PUMP POWER wire tap. If it never gets off zero at any key position (Run or crank) your problem is either wiring, the circuit opening/Fuel pump relay, or the efi main relay, or the fuse itself. If it has power in 1 position but not the other, suspect wiring, or possibly the airflow meter. fuel pump switch power is run thru the airflow meter, if its not hooked up, the fuel pump relay cannot be closed in the run position, or if its open internally or the contacts are bad.

    Sep 17, 2009 | 1991 Toyota Pickup

    5 Answers

    1991 ford f-150 fuel pump will not come on

    lets cut right thru the chase and go to the heart of the matter. what you most likely need is a new ecm which is the brain computer that tells everything in the motor what to do and you may have some corrosion on the ecm connectors that run to the wiring harness which in turn could effect your direct connection to the ecm's ability to communicate to the fuel system.

    Jul 26, 2009 | 2004 Ford F150

    1 Answer

    93 merc topaz feul pump wiring harness question

    The engine computer turns on the fuel pump for 3 seconds when you turn the key to "ON".
    If the engine does not start, the pump will not run.
    When you turn the key to "Start", the fuel pump runs all the time the key is held in start.
    When you turn the key on, it actiavtes the power relay, which provides power to the PCM or engine computer.
    The PCM then activates the fuel pump relay, sending power to the fuel pump.
    You should have one wire with 12V for 3 seconds in "run" position. This comes from the fuel pump relay to the inertia switch in the trunk and then to the fuel pump.
    You should have one ground wire. black
    One wire going to the fuel guage.
    You may have another ground iwre ging to a diode before going to ground.

    Mar 30, 2009 | 1993 Mercury Topaz

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