'94 940T wagon, 280k+.

This just started out of the blue and is getting worse.
Engine will die then catch under acceleration.
No codes are being thrown.
It is not related to how much fuel is in the tank, happens on full or low tank.
It DOES seem to be heat related, not likely to happen on a cool morning, more likely on a warm afternoon, even from a cold start (car sitting in sunny parking lot all day).
It will misfire after a turn, the CPS is only a year or two old & NOT split but I will check it.
It will do the same when accelerating from a stop.
It will even die when decelerating at a traffic light.

Initially, I was thinking FPR but that checks out fine. Next on my list is the power stage, I think I have an extra lying around somewhere.

Anything obvious I am missing?
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1999 E320 1994 F150 1989 560 SL 1986 560 SL (deceased) 1988 300 TE (departed) 1994 945T (daughter's) 1988 244DL (it lives!) 1986 242Ti (fallow) 1968 GT500KR (under restoration)