Engine Intermittent Power Loss Wot

I've had an intermittent power loss issue at wide open throttle and I'm stuck.

I can get car rolling and put into second (1500-1600 RPMs) and stomp it. It will hesitate and stumble a little (normalish) and then accelerate hard like normal. Then you can feel the loss of power all of a sudden (like wheel spin) and it will make a fluttering type sound.

It would clear up and then come back about three times through the RPM range all through the one gear. The car never stops pulling, just feels like you turned the A/C on then off. It is very frequent when motor is colder and more intermittent when motor is at operating temp.

I can half throttle all the way to redline in 2nd gear and it runs fine. Just when you "stomp it."

2003 GT, 123k miles, 3.73 gears

Been through 3 full tanks of fuel from two different stations (Shell and RaceTrac)

• Replaced EVAP thingy in passenger fender recently (had codes). Replaced hoses also.
• Replaced gas cap (codes).
• Cleaned MAF.
• Checked injectors (ohmed and unplugged)
• Checked COPs and have spark. Unplugged also to check change in RPM.
• Checked PCV, it rattles when shaken.
• Seafoamed it and put rest in gas tank.
• Replaced fuel pump (Delphi) a few hundred miles ago. Don't remember if changed filter.
• Unhooked and plugged EGR hose
• Unhooked MAF and drove, no change.

Motor does use oil and has a blue puff on take off if I idle at a redlight or so. I assume valve seals are the culprit.

Unhooked EGR. No change.

Will test the alternator. It was rebuilt less not too long ago.