1. Welcome to Jeeps.net!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Jeep discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Jeep owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Lost for ideas

Discussion in 'Wrangler YJ (1986-1995)' started by James95yj, Sep 3, 2016.

  1. Sep 3, 2016 at 11:43 AM
    #1
    James95yj

    James95yj [OP] New Member

    Joined:
    Sep 3, 2016
    Member:
    #160
    Messages:
    4
    Gender:
    Male
    First Name:
    James
    Vehicle:
    95 yj
    Need help my 95 yj is having issues. You turn the key it will crank over but won't start after 4 to 5 minutes the fuel pump relay will click multiple time and the check engine light will come on it will fire instantly after that. Any ideas been working on it nightly for a week
     
  2. Sep 3, 2016 at 7:45 PM
    #2
    C2T

    C2T Well-Known Member

    Joined:
    Jul 31, 2016
    Member:
    #42
    Messages:
    759
    Gender:
    Male
    First Name:
    Richard
    Helena, Montana
    Vehicle:
    Jeep
    2.5" AEV Dual Sport lift, 35" Treadwright Guard Dogs, Black Rock Wheels, AEV Front & Rear Bumpers with Tire Carrier, Fuel Caddy 10 gal. Aux. fuel tank, Warn 9.5ti, 125' synthetic winch line, front axle skid, 20" LED light bar , Bilstein Shocks, steel steering skidplate,
    Do you hear the fuel pump prime when you turn the key on (not starting)?
     
  3. Sep 3, 2016 at 10:35 PM
    #3
    James95yj

    James95yj [OP] New Member

    Joined:
    Sep 3, 2016
    Member:
    #160
    Messages:
    4
    Gender:
    Male
    First Name:
    James
    Vehicle:
    95 yj
    Not until the relay does the clicking thing
     
  4. Sep 4, 2016 at 6:48 AM
    #4
    C2T

    C2T Well-Known Member

    Joined:
    Jul 31, 2016
    Member:
    #42
    Messages:
    759
    Gender:
    Male
    First Name:
    Richard
    Helena, Montana
    Vehicle:
    Jeep
    2.5" AEV Dual Sport lift, 35" Treadwright Guard Dogs, Black Rock Wheels, AEV Front & Rear Bumpers with Tire Carrier, Fuel Caddy 10 gal. Aux. fuel tank, Warn 9.5ti, 125' synthetic winch line, front axle skid, 20" LED light bar , Bilstein Shocks, steel steering skidplate,
    The symptoms fit that of a ECU/PCM issue. This would cause the issue when the engine is cold but after that, you can turn off and start right back up without issues until the engine, or more accurately, the ECU/PCM is cold. Most of the common wisdom says to replace the ECU/PCM.
    - I say, test it first.

    "testing {the ECU} output is easy enough. Just find the pin that supplies the voltage to the fuel pump relay and check for voltage when the ignition is turned on and after the fuel pump activates. If it is low at first...VIOLA! We have a winner. If they are the same then the problem is likely elsewhere."

    ALTERNATIVE TEST (not as precise but easier to do at home)
    If I am correct the issue will continue to get worse as the temperature drops outside as it has to do with your ECU taking too long to warm up. A test some claim has worked is to take a blow dryer and warm up the ECU/PCM for about 10 minutes and then turn the key on... If your fuel pump works right away, the issue is the ECU/PCM. (The idea behind this is that the electronics get old and take longer to warm up and activate the power to the pump. The initial low voltage would also be the cause of the clicking of the one solenoid.)

    My best guess...good luck.
     
    OFFGRID likes this.
  5. Sep 13, 2016 at 6:51 PM
    #5
    C2T

    C2T Well-Known Member

    Joined:
    Jul 31, 2016
    Member:
    #42
    Messages:
    759
    Gender:
    Male
    First Name:
    Richard
    Helena, Montana
    Vehicle:
    Jeep
    2.5" AEV Dual Sport lift, 35" Treadwright Guard Dogs, Black Rock Wheels, AEV Front & Rear Bumpers with Tire Carrier, Fuel Caddy 10 gal. Aux. fuel tank, Warn 9.5ti, 125' synthetic winch line, front axle skid, 20" LED light bar , Bilstein Shocks, steel steering skidplate,
    Did you get this figured out?
     
  6. Sep 20, 2016 at 1:26 AM
    #6
    James95yj

    James95yj [OP] New Member

    Joined:
    Sep 3, 2016
    Member:
    #160
    Messages:
    4
    Gender:
    Male
    First Name:
    James
    Vehicle:
    95 yj
    Yes ordered a new ecu and solved the problem thank you
     
    OFFGRID and Bob like this.
  7. Sep 20, 2016 at 7:48 AM
    #7
    C2T

    C2T Well-Known Member

    Joined:
    Jul 31, 2016
    Member:
    #42
    Messages:
    759
    Gender:
    Male
    First Name:
    Richard
    Helena, Montana
    Vehicle:
    Jeep
    2.5" AEV Dual Sport lift, 35" Treadwright Guard Dogs, Black Rock Wheels, AEV Front & Rear Bumpers with Tire Carrier, Fuel Caddy 10 gal. Aux. fuel tank, Warn 9.5ti, 125' synthetic winch line, front axle skid, 20" LED light bar , Bilstein Shocks, steel steering skidplate,
    Glad it worked out for you. Back to jeepin'....


    Wheel Safe!!
     
To Top