okay guys im at a total loss on whats wrong, starting last week my 305 tbi 89 firebird started lurching at random and very inconsistently times where it just loses power and doesn't seem to respond at all to throttle, assuming it was an ignition issues i replaced the coil, cap and rotor and spark plugs (not wires yet) but it still does this and seems to get a little worse everyday, strange thing is it only seems to do it when the car is warmed up (about 10 min of driving)and in neutral i don't see it do it at all. the transition isn't slipping i believe because my rpm's seem to move in sync with the power. could this be a tv cable issue? something else im not considering? fuel pump and filter are new so i really don't thinks its fuel related.

 

Does it happen at a certain speed? Does it happen at a certain throttle position? Is it possible your transmission isn't downshifting as it should, or the converter isn't unlocking?

 

What is your fuel pressure when it's acting up?

What is the data stream showing when you connect a scan tool? Does the RPM plummet when the engine "lurches"? O2 sensor readings and crosscounts? MAP sensor reading? Anything else unusual?

At night, or dark garage--lift hood, let engine idle. Do the plug wires glow?

 

I had a very similar issue with my car that ended up being ignition related. Car ran fine when cold, but after it warmed up it sputtered and coughed all over the place. I had a shop do the repairs as I could not find the issue myself, and they didn't know specifically the cause either. This was after replacing the fuel pump myself too. I also replaced most of the ignition side as you did but still had the same issue before the shop fixed it. I have to think this is not being trans related. Since the plug wires are the last thing to replace, I would at least pull them one at a time and inspect them for burnt areas that could be grounding out. Also check them for continuity with a voltmeter to make sure they are sending proper signal. One last thing to check which may be a long shot is the ignition control module in the distributor. You can have a local parts store check it to see if it's bad.