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Discussion Starter #1
This just started this morning. No signs of it yesterday:
When I press on the accelerator with anything other then light pressure the engine gives me a surging type reaction. It doesnt cut out or die, and if I stay light on the excelleration it will slowly speed up. If I give it a good stomp it just goes into the surging action again. It acts like I was pressing on the gas, then letting go, and then pressing again, over and over.

Is this a sign of a dying fuel pump? Is there something wrong with the carb? Anything I should check for?

If it's of any relevance just last week I went to have it emissions tested and it failed for being to rich (high CO).
 

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It's very possible that your accelerator pump (in the carburetor) is malfunctioning, causing the carb. to mix extra fuel and gasoline when it isn't supposed to... Which, in turn, causes the car to surge

It COULD be the fuel pump. Is it mechanical or electrical?
 
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Discussion Starter #3
Talking to someone here at work about the problem and they suggested the accelerator pump as well. He didn't think it would be the fuel pump since it runs fine w/ a steady slow acceleration, even at high speeds.

Does the accelerator pump has mechanics that can break or get clogged?
 

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Does the accelerator pump has mechanics that can break or get clogged?

Depending on carb type, there is linkage that can wear/get misadjusted, a diaphragm/check ball which can fail and passageways/squirter nozzles which can get clogged up. There's also a check under the squirter which prevents venturi action past the nozzle from sucking fuel out of the passageway.

Post as much as you know about the carb, along with the transmission type

Also, check and report the curb idle rpm and timing reading, along with the timing reading at 3K rpm.
 
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Discussion Starter #5
From what I can read from the carb tag its a Motorcraft D0PF. The tag also has C5J19 on it.
Transmission is a automatic 3 speed.

When looking through the receipts of the previous owner he bought and installed a rebuilt kit in Feb of 2002. Could it need rebuilt again, already? Would it be benifical for me to buy another rebuild kit and try replacing the accelerator pump right off the bat?
 

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Any chance the carb looks like this? Or, maybe this?

If not, it's likely a 4300 and you have my sincerest condolences...*G*

Consider replacing it with an aftermarket carb if possible. What year is your car?
 
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Discussion Starter #7
It's neither of those. It's a 69 I6 1bbl carb. The only thing the shop guides show for 1bbl are autolite and carter, but nothing about Motorcraft.
 

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1V carbs are out of my league...never worked on one *G*

Maybe the inliner guys here can help. Try a new post referencing this one with something about an inline 1V carb in the title.

I'll bet it's accelerator pump but can't really help you to fix it.
 
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