Sticky throttle - is a spacer problem? - Vintage Mustang Forums
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post #1 of 3 (permalink) Old 05-26-2019, 02:38 PM Thread Starter
Join Date: Mar 2017
Location: Central Virginia
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Sticky throttle - is a spacer problem?

I have a 1966 convertible with a 289 4 Barrel. It was my Dad's car before it ended up in my garage. His throttle tended to stick (I'm using throttle just as a general term to explain the problem). When he hit the gas pedal the throttle would stick and he would have to feather the pedal to drop the RPM's. He couldn't figure out the cause so he ended up attaching springs to the pedal to counteract the sticking. This didn't seem to work very well though.

Two years ago I rebuilt the engine from the ground up with two mechanic friends. I replaced the carburetor with a rebuilt stock carb and most everything else was replaced. AND IT STILL STICKS!

The one thing I didn't replace was the spacer. Could that be the problem? Could the flaps in the carb get stuck on/in the spacer? Do I really need the spacer? Any thoughts? The engine just purrs but the throttle sticks constantly making it not very enjoyable to drive.



My Dad's '66 - now mine!
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post #2 of 3 (permalink) Old 05-26-2019, 02:48 PM
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Location: Poway, CA
Posts: 2,172
The spacer is how the PCV valve is plumbed. Yes I have seen throttle plates hit the edge of the spacer and cause a bit of sticking.

Also check the drivers side motor mount. If it is busted, the motor rocks on accel and that pull the throttle open more which leads to a runaway stuck throttle effect.

Everybody has to start some place
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post #3 of 3 (permalink) Old 05-26-2019, 03:13 PM
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Join Date: Mar 2012
Location: San Diego, Ca
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Throttle plates sticking on the paper gasket above the pcv plate/spacer? Get the air cleaner off along with the throttle return springs. Operate the throttle manually and see what's going on. Brian

5R09A 4 Speed GT Built 5/29/65
9T02R 4 Speed SCJ Built 9/19/68
Owner Driver Mechanic

Last edited by Brian Conway; 05-26-2019 at 03:16 PM.
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