severe stumbling on take off

[00 Ragtop Z]

The ragtop has developed a rather severe stumbling (in first and second gear particularly) when starting out or giving it a little more gas than usual (WOT simply does not work at all from a perfoamcne standpoint.). It was doing this earlier, I got a tuneup and new fuel filter (at 107,000 miles), and it improved for a while but now it's worse than ever at 111,000 miles.

It feels like fuel starvation, (it will stumble then surge the stumble then run okay) but for the life of me I can't figure out why it would happen many times but not always. It seems much worse after I have left the car sit for 4-5 days when I travel. Injectors? Dirty fuel?

Also, after I drive it a while on the highway or whatever, it seems to not stumble and surge as much until I let it sit again. Then I start the process over.

Suggestions????

[Joe 1320]

I would check the fuel pressure and volume first. If that checks ok, get it on a scanner and read the data stream. It will tell you whether the computer is trying to add fuel, trying to reduce fuel, etc. I could be any multitude of things.