Need help bad please.

[tex2010]

i have a 1996 eclipse spyder gst. it has slowly developed a misfire that i cant figure it out. i noticed about a month ago that at about 6200 rpm the tach would jump around(mostly towards 7k in 2-300rpm increments. i do not know how long it has been doing it before as i do not usually go past 5500 or so even when i am bein hard on it. its kinda like when the plug on the ignition control module comes a lil loose and has a bad tach signal. in the past 2 weeks it has slowly worked its way down to a consistent 4500-5k rpm miss. and occasionally down to 3600 or so. even backfires here and there. ive replaced plugs, wires, crank sensor, cam sensor and used a friends ignition control module, coil pack, and ecu. I AM COMPLETELY STUMPED. i really need someones help. if you have any ideas please share them. it will be greatly appreciated.
p.s. if your going to say boost leak or fuel keep in mind that the tach isnt just missing a beat and dropping, its literally jumping up and down(mostly up) and my A/F gauge is staying full green so it shouldnt be fuel cut. but if you know something that would help please tell me.

 

[dsmjunkie97]

Does your car still have the 7-bolt bottom end?

 

[97-gst]

alright go to advance get them to run a diagnostic scan and see whats goin on. I had a similar problem it was almost like i was hitting the rev limiter at 5500-6k. It was bad wiring to my coil on plug setup. I'd try that but you having to replace the crank sensor has me worried.

 

[tex2010]

yes still 7 bolt. and as for advance......i work there. no codes so there for the reader we have wont help. they dont supply us with the full diagnostic tools. just the top code reader models