So did you check the vacuum line to the EGR to see if it is clogged up?

BTW, I don't think unplugging the ECU with the battery connected would cause the problem, so you can stop beating yourself up over that IMHO.

You never got a misfire code?

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra