cars dies when brake pedal is pressed

Discussion in 'Technical' started by maverick7072, Mar 5, 2021.

  1. maverick7072

    maverick7072 Member

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    i decided to drive my maverick to work today. got 3 miles from my home and it shut down on me. i could jump start it from the solenoid switch but as i tapped the brake pedal it would shut back down ,so i unplugged the brake switch and drove it back home.just for curiosity i plugged it back up and the car started with the key switch and tapping the brake didn't shut it down.but I'havnet gotten it back on the road yet,any ideas what the problem could be
     
  2. Jaybee

    Jaybee Member

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    Did the ignition quit like a kill switch when you hit the brake, or did the engine die as you came to a stop? Does your car have an idle stop solenoid, a small, can-shaped electrical device which serves as your throttle stop?
     
  3. 71gold

    71gold Frank Cooper Supporting Member

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    mine did the same thing once...low battery voltage from alt. not charging. the exciter wire came unplugged.
    see if it dies when you turn the headlights on.
     
  4. maverick7072

    maverick7072 Member

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    i dont honestly rememeber if i hit the brake when it died going down the road but i did have a car in front of me that coul dhave caused me to hit the brake.but i do know when i jump started it on the fender in the parking lot it would go dead as soon as i tapped the brake pedal.so i unplugged the brake switch wire and started it back up and tapped the brakes and didn't die that time so i drove it home ,plugged the brake light switch back up and tapped the brakes and stayed running,then i turned the headlights on and tapped them again and still running ,Jay my car doesn't have a electric throttle stop . 71gold what s the exciter wire ?
     
  5. 71gold

    71gold Frank Cooper Supporting Member

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    it's a switched on 12 v feed to the alt. to turn it on so it will start charging. some alts. all you have to do is rev to 12-1500 RPMs and that excites the alt.
    my first experience with it we were on US 1 on the N.C./S.C. line at 2:00 in the morning...(39 degrees).
     
  6. maverick7072

    maverick7072 Member

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    it will be saturday before i have time to check anything else out on th maverick. so i need to check to see if that wire has came unplugged? i have tried turning the headlights back on and it didn't shut the car back down. could it be my alt. is trying to go out?
     
  7. Krazy Comet

    Krazy Comet Tom

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    The exciter circuit has no function once alt starts charging, it's only to begins the process.

    Anyway, unlike many internal regulator systems, there is no separate "exciter wire". At most, could be considered wire between Field term of alt and regulator, part of alt harness. Excitation is accomplished via circuit path through the regulator. If any of this circuitry is open, there will be no charge.

    My guess you have a weak alt or maybe just a bad regulator. I've had a couple over years that charged 10-12A at best. Were OK during daylight & minimal night use, but with heater running would discharge battery.


    fordcharge1970 001.jpg
     
  8. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    If you discover the alt. is your problem; may want to consider one wire unit. I have 130A. after market unit about 10 years, run elec. fan, AC and sub-woofer amp. I have no issues w/ all working at night -- one of the best upgrades I have made.
    Lastly, got rid of regulator and associated wiring on the fender panel..
     
  9. maverick7072

    maverick7072 Member

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    mojo where did u get your 1 wire alt ?
     
  10. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    Quality Power Product: 03/04/2010 several thousand miles later, no issues. If you plan to add any power consuming accessories, 45-55A alt. just won't be up to the job.
    I'm running V-belt 130A. #7758-130A on 302 base engine. Price at time was $150.00 shipped for CA to Illinois.
    Best money I've invested in the car.

    Ford 3G small case high output alternator (qualitypowerauto.com)
     
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  11. maverick7072

    maverick7072 Member

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    does th eone you purchased just have 1 hot wire and a ground ?
     
  12. dyent

    dyent Member

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    Mine was Tuff Stuff p/n: 7068 100amp 1 hot and 1 ground.......... got mine off eBay
    David
     
  13. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    Has one hot lug, no ground! Grounds to mount bracket, have no issues in the decade it's been operational. Running 4ga. hot to hot lug, have piece of heater hose over oil tube for assurance hot lug not being able short out. I could probably add ground wire by attaching to case fastener.
     
  14. maverick7072

    maverick7072 Member

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    what amp do you guys recommend i get for my mav i don't have a electric fan or fuel pump,no AC just heater or speakers or amp nothing extra
     
  15. 71gold

    71gold Frank Cooper Supporting Member

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    100+ amps.
     
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