Have 99 saturn SL2. car pulls left upon hard braking. replaced right front caliper which I thought was bad but didn't solve the problem. upon loosening of brake hose to right caliper, with a light brake pedal pressure there is immediate fluid flow. so I'm asumming the line is not restricted. Is it still possible that the rubber hose is defective? would problems with the back brakes be able to have this pulling effect? are there any valves in the fluid line that could be defective? thans

Assuming that the Tires for both Left and Right are:
1. Equal Sizes.
2. Both Properly Inflated - this is a common problem.
3. Have equal wear on them. Example: If the Left Tire is balding on the outside and the Right Tire is balding on the inside, this too is definite sign of an aligment issue; and will cause unequal braking.
Pulling left (or right) during a hard brake might actual mean your Wheel Alignment is way off. When you get one, get a 4-wheel and not just a 2-wheel alignment.
Also: you thought the right thing, but the Left Caliper or Left Brake Hose might also be bad (sticking) causing the left side to brake "harder" then the right side.
You can also Bleed the entire System (all four wheels) starting at the Right Rear, then Left Rear, then Front Right, followed by the Left Front.
Let me know if this helped, or if you have additional information or questions. Feel free to contact me at FixYa.com!