Bronco Hard To Starting

Discussion in 'Ford Trucks' started by Mad Max 4x4, Feb 14, 2008.

  1. Mad Max 4x4

    Mad Max 4x4 Member
    Messages: 36

    I have a 88 bronco thats doesn't want to start on the first try. It just turns over longer then i think it should. If i try a second time it starts right away. What could cause this? Also when the motor is warm the rpms go up and down up and down until i give a little gas or a couple of seconds pass.THANKS MAD MAX 4x4
  2. MrCarlson

    MrCarlson Junior Member
    from MM
    Messages: 18

    Do you have more details on the truck? I assume it is a fuel injected 302, but my memory is a little fuzzy on the late 80s trucks. How many miles are on it? Does it do it just when cold or warm too? any other issues with the truck that may be related?

    I think the obvious thing would be to do a basic tune up (plugs, wires, etc). Then make sure that you have strong batteries so it is turning over fine. Then, if it is fuel injected I would check the fuel pressure, a weak pump may cause a slow start. Does it help if you cycle the key a few times to give the fuel pump a little more chance to build up pressure?

    -Matt in MN
    97 F350 PS, flatbed, For Sale
    97 F250 PS, Boss 9'2" V plow
  3. dellwas

    dellwas Senior Member
    Messages: 369

    Fluctuating RPM can be a symptom of a vacum leak, particularily at idle, once you give it gas it builds up pressure.

  4. Redneck

    Redneck Senior Member
    Messages: 187

    I agree with delwas, check your fuel pump pressure, I think theres an IAC (idle air control) on that unit could cause the idle loping, next thing is look for broken or cracked vacume lines, also check the intake bolts making sure there all tight. give us an update once you do
  5. Milwaukee

    Milwaukee 2000 Club Member
    Messages: 2,179

    It almost exact to my cousin's car that would do that.

    We end replace spark plugs it was misfire, replace air filter it so dirty, clean IAC sensor it have those black gunk cause stuck not moving, clean exhaust's oxygen sensor it was so dirty, and dump all sea foam in gas tank.

    Then we use computer to scan car for problem now it work fine no misfire or problem.

    I just gave you if you try this then if it not then it must be another thing.
  6. OP
    Mad Max 4x4

    Mad Max 4x4 Member
    Messages: 36

    Its a stock rebuilt 302 every thing with a tune up is new, about 2,000 miles on it, tried to turn the key a couple of times before i try to start it it does the same thing only starts good when it turns over a second time i have 2 batterys dont know what to do. THANKS GUYS MAD MAX
  7. jjtmarineb2

    jjtmarineb2 Member
    Messages: 79

    Replace your fuel filter and see immediate results. As for the idle issue, clean the idle air control module with some carb cleaner. They are notorious for clogging up with carbon and getting stuck. Also check for vacuum leaks. You should be up and running great! :salute:
  8. Milwaukee

    Milwaukee 2000 Club Member
    Messages: 2,179

    My mistake we did replace fuel filter but most I was shock with my 79 f150 it clog fuel filter but we drove almost 500 miles until I feel that engine seem to ok but thought it should be strong so we went to Murray we couldn't find original one so we end get fram with clear see filter.

    I remove old fuel filter it leak brown thingy like goof on floor Now it have new fuel filter it work better now.

    When you do that then get sea foam from auto shop you would need that to help clean injector in engine to run better.
  9. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,589

    When you turn on the truck fist thing in the morning your should hear the relay click then a "vert" type sound when the regulator bleeds off pressure. Try turning the key on a few seconds then off and back on and try to start. The regulator is on the fuel rail with a vacuum line attached. With the truck running pull off the vacuum line. The idle should rise.
  10. AbsoluteH&L

    AbsoluteH&L Senior Member
    Messages: 566

    One more thing to try. The throttle position sensor. Had to do one once on my moms Tempo, But I am sure they were on most Fords around that time frame.