Hi,

I am a French guy living in San Francisco, very new to the Mustang world and I bought a nice 1967 289 three weeks ago. Everything is fine with the car (new interior, nice color, amazing sound) but I have a problem and would like to have your opinion.

When I am stopped and start moving, I have to accelerate very slowly for 4 to 5 seconds otherwise I have the feeling that the engine will stop. Everything is fine when I do not accelerate (it does not stop) and when I am moving (I have pretty good performances on the highway). It's only between 0-20 mph that it happens. Note that it is both when the engine is cold and warm

Do you have any idea about what it could be?

Thanks a lot!

 

I'd start by pulling off your air cleaner and check to see if your accelerator pump is working. Look down the carb and manually pull the accelerator and listen/look for gas squirting as you do this.

Let us know...it could be a number of things but this will cross at least one off.

 

it certainly sounds like a carb. issue to me. what is on there? you could have a 2 barrel autolite or a 4 barrel edelbrock, holley, autolite, etc.

 

Yeah, 10 to 1 says it's the accelerator pump, or something else carb related

 

Congradulations on your Mustang!

And I agree with the prevailing opinion that your problem is probably the accelerator pump,,,

Or, your ignition timing might be a little retarded.

 

Thank you all for your answers

Is changing the accelerator pump something difficult/expensive? Note that unfortunately I am a beginner and would not be able to do it myself (at least for now )

 

Accelerator pumps are'nt difficult to replace parts on. It may be as simple on your's as something just isn't set right, or hooked up.

 

The difficulty will depend on which carburator is on your car, some brands are easier than others, if you have a chance, post a couple of photo's of your carburator, one from the front on each side..

the difficulty level from brand to brandvaries from very simple tomedium difficult for a person with no carb experience...

 

The mechanic was too busy today so I decided to investigate! As said before, I am a pure newbie.

I decided to remove the air filter to have a look at the carburetor which seems to be a Motorcraft 2100D (if you have some pictures, I may be able to recognize it). I found something strange about the "Choke plate": it never moves (even when someone accelerates motor running or not) and thus stay open all the time.

Is that normal? Could it be related to the fact that the engine works way better when the car is already moving? It's maybe a pure newbie question but I'm learning

One more thing, there is an oil leak. I parked the car somewhere for 5 minutes and there was drops under the engine and little ones from the front of the car to the rear. Note that the engine was running...

Thanks a lot

 

No thats not normal. The choke plate is supposed to open as the engine/choke gets warmer. I don't know much about carb's myself, but I think its a safe assumption that the choke is either broken, or not hooked up. If its electric the wire could not be getting power, or disconnected. And if its manual, who knows, coulda just came loose. It could simply be a broken choke in general as stated before.

good luck! nice looking car!