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  1. #1

    Default Choke Won't Reset When Cold on 1985 GT

    Hi All:

    I thought I had this issue solved awhile back when I had a tech do the adjustment. When I asked what he had done to correct the issue, I thought that he said that possibly a linkage need lubricated? As mentioned the car had been running great until I went to put it in storage for the winter this weekend, and when I started it to move it, the prior problem was back.

    The tech who made the original adjustment said that there was nothing wrong with the stock unit as I was preparing to replace it, that it just needed a minor adjustment. My cold starting process is always the same: push the accelerator once to get some fuel into the carb and set the choke, turn the key, and she usually starts on high idle. I usually let her run on high until I get to the end of the driveway, and when I first apply the throttle, and then it moves down to the next "medium" idle. Shortly thereafter, it moves to normal idle.

    This last time, I can only assume that the choke didn't set for a cold start, as it must have been running lean while cold. While this is going on, it will not idle at all, stalls when the car is stopped, and is difficult to keep running when not rolling. (Thank goodness it's a manual!). When I back off the gas, it cracks and pops and I seem to smell the catalytic converters also. I'm sure it's running too lean. When I got to the storage site, I removed the air filter and the choke plate was wide open and won't move with any manipulation.

    Is there an easy solution that I can practice when this happens so I don't have to get a third party involved?

    Thanks much.

  2. #2
    FEP Super Member xctasy's Avatar
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    Sorry for the corny words. Fords carb cars have oh, about 90 to 105 vac and emissions devices all relayed together. If tjere are no hose leaks or common working surfaces binding due to lay offs, they normally work fine. Problems are normally electrical, where Ford decided to use low voltages to operate two parts the Choke and the Throttle Kicker.

    So tje process is listed on the Engine and Vac Troubke Shooting Manual down to the minute detail, but here is thw general gist of it.

    Your car has a choke pulldown, which quickly deactivates the fast idle facility the choke Should always provide when tjr engine is cold.

    This is set with a Mitivac vacuum hand vac pump.

    It is dialed to an indicated reading if I recall, 20 in Hg on the scale, with vac applied at Point A on the emission detail schematic and the process is intimated on your VECI label under the hood.

    There is a Vacum Operated Throttle Modulator ( called VOTM hereon), a Hot Engine Idle Compensator (HEIC), present on all 4180 C 4bbls and certainly if your car has A/C.

    The three parts work in cahoots to balance cold starts by spiking the idle speed, then really quickly backing it off when the electric choke expands. The internal choke wire which is 7 volt fed from the alternator must be energising. It seams to be .

    Then the choke pulldown vacuum has to be reset. It probably hasnt been rechecked.

    The working surface of what is called the VOTM must be clean and working freely. It may not have been, and that is common. So WD40 or Dryglide or Magnalube is a good thing to add to the working surface of the dashpot which sits in fronr of the radiator side of the throttle arm. Lastly, if A/C equiped, the throttle kicker operates on the VOTM.

  3. #3
    FEP Power Member 85stanggt's Avatar
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    You won't be able to close the choke flap yourself without lifting the throttle off the dashpot. If you look at the linkage behind the electric choke cap, there is a screw on the same primary throttle rod. When the throttle is closed, that is sitting against the fast idle cam of the choke, so when you try to close the choke flap, the cam will run into the screw on the primary throttle rod.

    Spray carb cleaner all over the linkage behind the choke there to get everything cleaned up. If you use lubricant, it will collect dust and dirt and end up binding up again.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

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