Classic/Antique Car Repair/Carburator issue

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Expert: - 5/2/2011


Question
I have a 1966 Ford Mustang with an autolite 1100.  The issue I am having is when I turn off the ignition the car sputters a few times before it shuts off.

Answer
The most common cause of this is the idle speed set too high. This allows the throttle plate to be open a bit too far and when the ignition is cut off to stop the engine a little too much air and fuel is drawn in as the engine slows to a stop. This fuel and air hits the hot combustion chambers and causes combustion or dieseling. Depending which engine and transmission you have the idle speed ranges between 500 RPM and and 675 RPM. The second cause could be a slight vacuum leak somewhere in the intake system. If you let me know which engine transmission package that you have I can give you the correct idle speed setting.  

Classic/Antique Car Repair

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Brad Sears

Expertise

All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.

Experience

Automotive tech instructor. Syndicated auto columnist 1970's though the early 1990's. Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's TV Show "Last Chance Garage" 1980's PBS-TV syndicated. Auto instructor for the following companies: Fram Autolyte Holly Carter AMF Ford Motor University Of Conn Blue Hills Technical School Sugar River Technical Center Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.

Publications
Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.

Education/Credentials
More than I care to remember. Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.

Awards and Honors
Moto Award winner. And much more.

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