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Discussion Starter #1 (Edited)
My 67 Mustang with a 200 CID six, will not idle when it is warm. The story started when I backed it out of the garage, and noticed clear liquid on the garage floor. It was gas. I looked underneath the car , and gas was dripping from the fuel pump.

I replaced the fuel pump with a Airtex brand from the local auto parts store. That is when it started not idling when the engine is warm, and the choke is fully open, It starts great when it is cold, and the choke is closed. It goes to fast idle and runs smooth. I did some research, and some people have had problems with Airtex fuel pumps. I ordered a fuel pump made by Carter. People seem to have had good luck with this pump. The new fuel pump did not change anything.

The engine ran great before the fuel pump was changed. I replaced the fuel filter, that did not do anything, I cannot find a vacuum leak.

It has a Autolite 1100 carb that has been rebuilt by Pony Carbs 2 years ago. It has not had any problems before this

I have to adjust the idle screw to max just to keep the engine running. It surges rpm's up and down. The mixture screw has little effect. If you put it in drive, it dies.
If I manually move the choke toward the closed position, the engine rpm increases. It is 76 degrees outside, and the engine is warm. Shouldn't the choke be fully open? The temp gage shows about 1/4 in the warm area. Should I adjust the choke? It ran great all summer, and fall.
Any ideas?

Thanks
 

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Discussion Starter #2
More info.

It is not the fuel pump, tried several. I put a tach on the engine, and started it while cold. The rpm's were about 1800. The choke slowly opened , and I watched the rpm's slowly fall, at about 10 minutes, the rpm's slowly fell until it got about 800, and it dies. It runs smooth while cold at fast idle, but begans to run rough as the rpm's fall.

This all started from a leaking fuel filter. There is a inline fuel filter at the carb, I can't see how trash could have gotten into the carb.

I am out of ideas.
 

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Discussion Starter #5 (Edited)
The Answer!

When the fuel pump failed, it plugged the idle circuit in the Carb. It is a Autolite 1100 that was rebuilt years ago by Pony Carbs. A tech at Pony Carbs had me try several things to try to clean the trash out of the carb, but it did not help. No amount of flushing would clean out the passages. I sent them the carb last summer, and it was rebuilt. It came back looking like it was new. I was impressed. The engine ran great as soon as the carb was installed. I installed a inline Fram fuel filter to hopefully prevent this from occuring again. I replaced the Airtex pump with a Carter pump after hearing bad reviews about the Airtex pump. I believed the installed fuel filter that screws into the carb was really a fuel filter. It is only a coarse screen.

I was sad to hear Pony Carbs shut down after the death of the owner. I talked to him when I sent the Carb.
 
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