High Idle Woes

Discussion in '1974 - 1978 Mustang II Talk & Tech' started by Dr Black, Mar 8, 2014.


  1. Dr Black

    Dr Black New Member

    Joined:
    Oct 21, 2013
    Messages:
    19
    Likes Received:
    0
    Trophy Points:
    2
    Hi guys, been awhile but I figured I'd post to pick your brains. Has anyone dealt with high idling? I've limited the issue to be the carburetor. I have it set to idle the correct way on start but once you hit the gas it goes into "race mode" and wont come down. I have the carb "rebuilt" but I'm beginning to wonder if it was done correctly. My only other though is that the choke isnt working correctly. Its an edlebrock with an electric choke, on an edlebrock manifold. Does any one else use electric chokes, or should I look into trying to get the manual choke up and running (bought it not realizing the manual choke wire was cut/ or what a manual choke was for that matter). Any ideas would be greatly appreciated and thank you for reading.
    #1
  2. jozsefsz

    jozsefsz Active Member

    Joined:
    Aug 11, 2013
    Messages:
    181
    Likes Received:
    17
    Trophy Points:
    29
    Sounds like it could be the choke. Observe the choke plate on top of the carb - when the car is fully warm the plate should be completely vertical. If it's not, then the car will still be riding on the fast-idle cam and won't come down until it's properly open. The choke pull-off could also be malfunctioning (it opens the choke slightly as soon as the car starts up).

    As the engine warms up, the bi-metal coil inside the electric choke cap opens the choke, and a stomp or two on the gas pedal will have it idle down. If it's an electrically heated choke make sure you have voltage at it. Some electrically heated coils also have supplemental heat coming from a tube that goes to the exhaust or from coolant (usually stock though and not an aftermarket Edelbrock). In your case it's most likely just an electric choke cap -- check that it has voltage, and that the choke opens as the car warms up.

    Personally I'm not a fan of electric chokes. They seem to work o.k. in areas with mild weather, in my part of the U.S. it can be 10 below one day and 60 degrees the next. So that made it an exercise of constantly adjusting the choke cap -- not enough and it wouldn't start on a cold day, too much and it never idles down and wastes a bunch of gas (fouling the plugs while it's at it). Electric chokes imho were a lame attempt at automation before EFI, much like the ton of other vacuum-operated solenoids and valves throughout the car cluttering it up and making it unreliable.

    I much prefer an old-fashioned manual choke. You control if / when it opens or closes, and you always know where it sits. Pull it out until it starts up, push it in a little, tap the gas, and close it up once it keeps running without stalling. You can still get the cable / conversion kit for about $20.
    #2
  3. Dr Black

    Dr Black New Member

    Joined:
    Oct 21, 2013
    Messages:
    19
    Likes Received:
    0
    Trophy Points:
    2
    Thanks for the reply! I was able to get it to a drive-able, but I have to baby the gas so that way it doesnt stall. All in all I'm happy to just have gotten it that far. I drove it and it renewed my desire to keep the car. Where can I get the conversion kit? I also live in one of the less weather friendly areas of the US and I am hoping to get Delilah up to my daily driver. I am not looking forward to trying to replace the speakers and finding a radio.
    #3
  4. jozsefsz

    jozsefsz Active Member

    Joined:
    Aug 11, 2013
    Messages:
    181
    Likes Received:
    17
    Trophy Points:
    29
    #4

Share This Page