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Frankenbuild will rough start and promptly die.

Discussion in 'Cherokee' started by Oogie, Nov 11, 2016.

  1. Nov 11, 2016 at 10:25 AM
    #1
    Oogie

    Oogie [OP] Member

    Joined:
    Sep 11, 2016
    Member:
    #202
    Messages:
    9
    Gender:
    Male
    First Name:
    Brett / Samm
    Flastaff / HB
    Vehicle:
    89 xj Frankenstein
    98 motor, sye, 8.8 LSD, 4.10 gears
    I recently upgraded by getting rid of my old 89 xj body and swapped my motor transmission and tcase over to a 96 xj. The old motor and everything worked just fine in the 89. Now the motor takes a little to turn over fires up idles rough for a few seconds then dies. The smoke coming out of the exhaust smells very rich but could be because it semi floods in between tries. The motor is a 98 the transmission is a 90 and the tcase is a 89. Here is a list of all things that have been done.
    • new pcm
    • new distributor, cap, rotor, wires, coil, spark plugs
    • new map sensor
    • new fuel pump, filter, strainer
    • bigger 4awg grounds
    • slightly better but still not amazing injectors
    • swapped over CPS for the OBDII
    There is fuel pressure and spark. The engine codes from the dash gives me a distributor sync sensor. My friends code reader said no codes but we will retry with the new pcm. The map sensor reads 4.7 with the engine off and when unplugged reads 9.4 (or something like that) even with the new map sensor. We think it is either a bad ground for the computer or map sensor, bad vacuum leak, or loose intake manifold or throttle body. I cleaned the IAC but it still may be bad. Checked all fuses in the hood and under the dash. If there are any ideas of what could be wrong please chime in this has become very frustrating for me. I can get a video later tonight when I am off work.
     
  2. Nov 14, 2016 at 10:48 AM
    #2
    Bob

    Bob Well-Known Member Moderator

    Joined:
    Jul 18, 2016
    Member:
    #1
    Messages:
    785
    Gender:
    Male
    You make any progress on this?
     
  3. Nov 14, 2016 at 4:46 PM
    #3
    Oogie

    Oogie [OP] Member

    Joined:
    Sep 11, 2016
    Member:
    #202
    Messages:
    9
    Gender:
    Male
    First Name:
    Brett / Samm
    Flastaff / HB
    Vehicle:
    89 xj Frankenstein
    98 motor, sye, 8.8 LSD, 4.10 gears
    put fuel pressure tester on it and replaced the fuel pressure regulator but now will not crank over or even try to. our guess is possibly bad neutral safety switch
     
  4. Nov 18, 2016 at 9:16 AM
    #4
    Oogie

    Oogie [OP] Member

    Joined:
    Sep 11, 2016
    Member:
    #202
    Messages:
    9
    Gender:
    Male
    First Name:
    Brett / Samm
    Flastaff / HB
    Vehicle:
    89 xj Frankenstein
    98 motor, sye, 8.8 LSD, 4.10 gears
    nss was bad still just cranks and won't stay on ill post a video soon. my code reader says fail to communicate but works with my taco. friends code reader shows no issues at least it didn't the other day. cold possibly be the cps but it didn't throw a code earlier.
     
  5. Nov 19, 2016 at 1:26 PM
    #5
    Oogie

    Oogie [OP] Member

    Joined:
    Sep 11, 2016
    Member:
    #202
    Messages:
    9
    Gender:
    Male
    First Name:
    Brett / Samm
    Flastaff / HB
    Vehicle:
    89 xj Frankenstein
    98 motor, sye, 8.8 LSD, 4.10 gears
    code reader gets power but fails to communicate. checked injector and cps with multimeter they are good unplugged all sensors still no communication port it getting power at both grounds. might switch back to old computer. obd port looks ok but i will use connection cleaner on everything
     

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