Don't buy a new carburetor if you can get away with just a new choke pull-off.

Dear Car Talk | Feb 01, 1993
Dear Tom and Ray:
Emily
RAY: I would have said "I'll go home and get the money right now. Hop around on one foot until I get back."
TOM: All you need is a choke pull-off, Emily. These are the classic symptoms.
RAY: The choke pull-off is a small, vacuum operated device that "pulls the choke off" (opens the choke) once the car has started. If it's sticking or broken, the choke stays closed too long, and your mixture stays way too rich (too much gasoline and not enough air).
TOM: And the classic sign of a mixture that's too rich is black smoke pouring out the tail pipe.
RAY: So take the car to a mechanic you trust, Emily, and ask him to check the choke pull-off. If that's the problem, it'll cost you $50, not $500.
TOM: And send half of that $450 savings to my favorite charity, the Crash Test Dummies Widows and Orphans Fund, Tom Magliozzi, Treasurer.
Emily
RAY: I would have said "I'll go home and get the money right now. Hop around on one foot until I get back."
TOM: All you need is a choke pull-off, Emily. These are the classic symptoms.
RAY: The choke pull-off is a small, vacuum operated device that "pulls the choke off" (opens the choke) once the car has started. If it's sticking or broken, the choke stays closed too long, and your mixture stays way too rich (too much gasoline and not enough air).
TOM: And the classic sign of a mixture that's too rich is black smoke pouring out the tail pipe.
RAY: So take the car to a mechanic you trust, Emily, and ask him to check the choke pull-off. If that's the problem, it'll cost you $50, not $500.
TOM: And send half of that $450 savings to my favorite charity, the Crash Test Dummies Widows and Orphans Fund, Tom Magliozzi, Treasurer.
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