Won't start
 

I have a 95 4runner I replaced the starter and battery i cleaned the connections and grounds and it won't start. When I turn it over the starter engages but won't turn over. Can any one tell me why

Your terminology is confusing,
Does the engine crank, or does the starter lock up and fail to turn the engine???

Yeah, I can't figure out what you're saying here either.

You turn the key to 'start' and.. it clicks but nothing else? Does it click or clunk? Do the lights dim out when you're doing that? Does the motor move at all?

Was it doing that before you changed the starter - and that's why you replaced the starter?

Exactly. Was is starting fine before, but now that you did the work, it's not? Or you did the work because it wasn't starting?

Typical dirty/corroded battery terminal symptoms are either nothing when you turn the key, maybe a click, maybe even a sizzling sound and some smoke, but the starter doesn't move. Typical starter issues would be just a click but no movement, or you hear the starter spin but not engage the engine flywheel, or the starter spins out a little ways but not far enough and just grinds the flywheel. When the issue is likely not the starter or the battery, the starter moves, engages the engine flywheel, the engine turns, but doesn't fire.

People will need to know exactly what's happening before they can do much good trouble shooting.

If the starter engages but won't turn the engine after you have done all those things, It is either:
The connection from Neg terminal to the block (not just the body).
The connection from the Pos terminal to the starter terminal.
The starter itself is not solidly mounted (grounded).
You didn't bench test the starter before you put it in and its bad.
The engine/starter is binding for some reason. Can you turn the engine manually?

A little inspection and some jumper cables can eliminate most of those.

thank you you were correct with your input i was able to figure out the problem