Had the tranny shop that did my rebuild go over the tranny again. Biggest problem is that the flare is not consistent - doesn't happen every day - and they couldn't duplicate it. They played with the TPS and checked all other electrical systems, fluid pressures, etc. and everything came back fine. Good guy though - agreed to warranty me 6 more months (actually expired) to watch for worsening problems.
BTW - tried disconnecting the resistor and did not like the way the transmission shifted at all - very abrupt especially on the down shifts. Plugged 'er back in right away! Also, to answer the question - the flare is typically 1-2000 rpm when it happens.
I guess we'll see if time brings on new problems or if the TPS adjustment made the difference - haven't had a flare since .
