These are the important parameters. You need something that will give you live data for these sensors and record data for later referencing.

If you have a laptop, you can't go wrong with AutoTap software. It will scan every parameter you need to know, including a lot of transmission info that other scantools omit. AutoTap is available from many different sources... Google it and see what kind of prices you can find. You want the package that will scan for GM enhanced parameters.

There are also stand-alone scantools. AutoXray makes a good line... the EZ Scan 4000, 5000, or 6000 will give you what you're looking for, but I think only the 5000 and 6000 come standard with GM enhanced parameters. The 4000 must be upgraded for $50 to scan the enhanced stuff. Actron also makes scanners that will do what you're looking for. The important thing, no matter what brand you choose, is to find one that includes GM enhanced parameters and is OBD2 (which is the kind of plug you have on your car).

Being a 97, let'* not forget AutoEnginutiy and HP Tuners.

Personally.. I'd say let'* stop where we are for a moment and look at what we have. You have a car that runs poorly, pull the plugs one by one and look at them. If one is misfiring, you should be able to tell that one looks differently than the others. This is a free diagnosis to try and determine which cylinder is having an issue.

Then.. get an ohm meter which most have laying around, or borrow one. Test the coils per the Techinfo article. Another free diagnosis test.

Start the car..listen for exhaust leaks... look over the EGR and the pipes going to it. Free again.

Take some pictures of this engine for us.. it'* amazing what some can spot in a picture. Maybe it'* a disconnected sensor you aren't seeing. Check all the connectors.

So with the AutoTap software is that all i need? Or would i need the scanner and the software? I do posses a laptop that i could use so which package would i need?

thanks.