mazda mx6 dyin out bad idle no power, boggin?

[Kenny]

I have a 93 mazda mx6 today i went to take it out and it didnt start so i popped the hood and the Neg cable that hooks into the terminal was loose so i tightened it up and when to start the car. it started but then died in about a second.. so then I figures out if i turn the ignition to the ON position and leave it there for about 5 seconds i hear a " click click" then turn the key over and it starts, but the engine light stays on. when i am just sitting there the idle is going up and down between 400 and 800 rmps. and when I get going about 80km/h and drop it to thrid gear and hammer on it it just bogs, i can do that to every gear just take of hard and it bogs??? When i go to stop at a intersection it will rev right down to 200 rmps then go back up..while i had the car running i took the spark plus wires of one by one to see if they where working and everyone i took of the engine reacted to it.. but the 2 plugs closes to the right so by the alternator and the belts were wet with oil.. and the other 2 but the batter side (left) were crisp dry like they should be?? any info on the car would be great! it is a 2l 4 cylinder DOHC 5 spd standard thanks alot guys