new transmission on 1990 Mazda 626

we just replaced the transmission and i noticed that at times shifting from 2nd to 3rd gear revs the engine up before it engages. it occurs intermittently. also, there are moments that when you turn the ignition the engine when start and the "hold" light would be blinking. but when i try to move the shifter from park to gear ('on' key position) it will crank the next time. the manual says it could be the electronic control on the transmission. what could be the causes so i can have them checked by mechanic. i still have a 90-day warranty on the transmission and labor.

thank you.

Asked by for the 1990 Mazda 626
I would have to say bring it back to the shop that just overhauled the transmission and let them diagnoise what is going on. I hope the transmission cooler and lines were properly flushed to prevent debris from the bad transmission from having entered your new transmission. 626 are not known for terribly reliable transmissions.