The check engine soon light on?

Thank you for everything

Would the vss cause the black smoke out of tale pipe when reving the engine?

A month ago. Just changed plugs, wires, dist. Cap and rotor button

The ecc conection under the hood left side towards fire wall. Here's how I tried to jump it.

It's still not showing me a code. When I hook it up this way the check engine light stays on. That's why I got my friends scanner and it still did'nt show anything.

How do I check that?

Sorry i'm not sure what you meen about pin-outs or sti. Where is the computer located on that car?

Thank you, by the time I got to your response it got dark. I'll have to check it tomorrow. With no light it's a little difficult.

Hi, I have a 1991 Merc Sable LS with 122,000 miles. I've had a bunch of problems with it since i've had it, brakes, radiator, alternator, all of which have been taken care of. Recently, I filled up the overflow tank with antifreeze because I was going on a trip and I felt like it was a good idea. Car drove fine during the trip up, and on the way back a couple days later, while getting gas I noticed the car was leaking antifreeze. I had to go home at that moment, so I drove home carefully watching the heat. Since then the car has had absolutely no problem overheating so I figured it was just the overflow tank because of that. However, recently the check engine light has been coming off and on, and the rpm's while seeming a bit more "normal" than usual are not normal for my car. While in park it is now idling at 1000 rpms rather than the normal 2000 and it just feels wierd while it is shifting. The car has always grabbed while shifting so I normally don't think anything of it, but it feels different, and it is coupled with antifreeze leaks and the check engine light. The car drives like a dream on the highway but city driving is like a nightmare. I'm taking it to the mechanic on thursday, but i'm nervous and really don't want to wait till then to figure out what it is.
Please help!