When I start from a dead stop the car takes off fine and whenI hit about 10 mph it hestitates (feels like ithas no power)for a second or two and then kicks in just fine-I know it is a minor problem but it bothers me.
Any ideas whatI should check first/
It is a a 289 automatic-I changed the plugs about a month ago.
Thanks Scott

 

Try running that car like it is stolen once. Push the gas pedal all the way to the floor until it shifts into 2nd. Now, did you notice the same hesitation? What I am getting to here is that your
C4 may be shifting too soon and needs to be adjusted so that it shifts into 2nd gear at around 20 or so. Get back with the results.

 

And where did you learn to steal cars?
Hotwire Jim

 

I learned to hot wire tractors when I was a kid on the farm because the keys always got lost or rusted out and we were too friggin poor to buy a new ignition kit. That knowledge bled over into my own old cars that I bought because they were cheap and I was poor. I bought a 1957 Cadillac in 1967 that was not running for 50 bux. I got it running by hotwiring it, bought the cylinder and keys and sold it for 500 the next day. If that car is still running and in good shape today, it is probably worth more than most of our mustangs.

 

My car has the same hesitation problem. It's not shifting early, and it only happens until it's been warm for a few minutes. My guess is still the transition circuit of the carb..?

 

My car is not shifting early-what is the transition curcuit?
any easy cheap quick remedies?

 

You can try to use some carb cleaner (probably won't help much) but everyone else'll probably recommend a carb rebuild.

 

Yep. sounds like a carb rebuild is in order.