1969 coupe throttle sticking

[kennygunit 10]

Hello,

 

I am having a problem with my 1969 mustangs throttle sticking (302 2bbl carb). When im driving, the accelerator pedal will randomly get stuck, and it takes a while for it to go back normal. Sometimes it won't go back at all until i rev it, try and brake, or mess with the throttle cable attacked to the carb.

 

I've had times where i think there isn't any throttle on the carb, and when i try to turn it off, its obvious that the car is still trying to run, even with the key out.

 

My guess is that there is something obstructing the throttle cable from moving, but with a quick glance at night, everything looks ok.

 

Any suggestions?

 

Thanks.

 

 

P.S. Are there any upgrades to this system that will make it more reliable and a lot safer?

[LindenBruce 27]

Well, first don't drive the beast until you get this issue resolved. An accident could be in your very near future. Now, check your return spring and make sure it is correctly attached. Then disconnect your throttle cable and manually, with the engine off, work your throttle buy hand and make sure it's not binding. And last but not least if those two are fine and dandy, replace your throttle cable. Since it IS a cable, it is most likely fraid inside and the little pieces of broken wire are hanging up inside the plastic tube. Also, do you have floor matts? They too maybe causing an issue. Bruce

[jholmes217 65]

Mine was sticking too until last weekend. I replaced the old stretched out single spring with a double spring and it's fine now. I don't think that would fix your idleing after the ignition is shut off though. I'll have to break open my books after work and see what they say. I've fixed that problem before, but it was in the late 1980's and I don't remember the cause or the fix.

[kennygunit 10]

Where did you get the right springs for the job?

 

Also, i think the idling problem is because of the accelerator problem.

[LindenBruce 27]

If your idle is set to high, or as you are saying your throttle is sticking, then it could cause what is known as "dieseling" when you shut off your engine. The engine wants to continue running but makes a alot of God awful banging knocking noises before finally dying. Carbon deposits on your piston tops or advanced timing could also cause this issue. Bruce

[jholmes217 65]

"Dieseling"! That's the term I was trying to remember, and your right Bruce. It was a timing issue that caused it om my car way back when.

[LindenBruce 27]

Hey, I'm just glad I could help. And you are all welcome. Bruce

[DeadStang 0]

The actual cable from the carburetor bracket to the accelerator pedal us usually not the problem. It's the worn-out bushings and such in your carburetor itself. If things aren't too bad, swapping the return spring for a stronger one, or using two, will solve the problem. You can just go to Napa or Schuck's and get a multi-pack of different diameter and length springs for a few $$$, then find one that is a little stronger than the current one to replace it with.

 

I think dieseling can be timing or idle speed.

[Big Secz 26]

I would recommend increasing tension on the return spring, buying a new perhaps shorter spring, and spraying WD 40 on the cam spring of the carb. My throttle stuck on me a year a go and it was the cam spring that was causing the problem. I sprayed it down with WD 40 and moved the throttle back and forth to work the oil in and I haven't had a problem since.

[maxum96 32]

Throttle cables are pretty cheap. I think they're around $20 from the Mustang shops.

[jholmes217 65]

Where did you get the right springs for the job?

 

Also, i think the idling problem is because of the accelerator problem.

 

Here's an example of what I used. I like the safety of two springs, but its definitely not a stock looking appearance for a restoration.

 

http://www.summitracing.com/parts/SUM-G1320/

[rangerdoc 22]

That's a pretty good idea, simply for the safety aspect of things.