I have the same exact problem. I decided it was bad injectors coupled with mediocre compression (I have some blowby) and a busted glow plug relay. I do the exact same thing, step on the pedal a bit for 5 seconds until it evens out, and I have replaced almost exactly what you have.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth