how do i tell if my distributor is bad... no spark to plugs need help all plug connections were checked but i have no spark please help

 

You can visually inspect the cap and rotor, and then check the coil and ignitor with a multi-meter. The distributor housing itself usually doesn't go bad unless a bearing fails, which makes the rotor spin out of balance and will destroy itself and the cap, so it is readily apparent most of the time when the bearing fails.

But the internals; coil, ignitor, rotor, and cap are all wear items that will fail over time during normal use. I am still running on a Autozone coil for 3 years now, and it was pretty cheap. They will test your old one, but remember, they are in business to sell you parts.