Normally this is caused by warped brake rotors.
Brakes on a Dodge Colt? It would depend on what is wrong with them, what they are doing or not doing.
Try having your tires balanced and rotated. I used to have a car that would shake very bad when applying the brakes and I did everything you did. Then a guy told me to have my tires balanced and rotated and it fixed it until the tires became unbalanced again.
Could be,Tire(s) out of balance, A worn tie-rod end (s),
STICKING BRAKE CALIPER
Frozen brake caliper
I would advise bringing your car to a mechanic as quickly as possible. Your brakes could fail. This puts you at a high risk for injury or even death.
I believe that would be a 3/8 Allen wrench. -Very common on Dodge /Plym brakes.
Never.
check the motor mounts
Warped brake rotor.Warped brake rotor.
New brakes have nothing to do with it. The prolem is with the Anti-lock Brake System, and not the brakes themselves. Take it to a professional.
Who checked them and how were they checked? Pulsing ONLY when you use the brakes is just about always the rotors. You might want to check for a bent wheel, but that would be an almost constant vibration.