Off-idle stumble resulting from ported EGR

[John T Stein]

Since this seems to be the time for EGR-related correspondence, has 
anyone come up with an effective method for eliminating the stumble 
that seems to be normal for GM engines with TBI and port-controlled 
(not PWM controlled) EGR??  I have had three such engines, a 2 L and 
2.5 L four and the 2.8 L v6 and they all exhibit the same faltering 
just as the throttle place goes off-idle. It seems as if the engine 
just can't cope smoothly with the rapid dilution of charge that occurs as the 
throttle plate uncovers the EGR port in the TBI.

 Disconnecting the EGR solves the problem but is obviously NOT a viable solution.

Any experience, suggestions??

Thanks, 
John