Lately my transmission seems to be screwing up. It happens mostly when first accelerating seems like it doesn't want to change into 2nd gear. It shakes violently and if i press the gas, it doesn't accelerate. Sometimes it will eventually catch and accelerate, but other times i will have to cut the car off, let the codes clear, and restart; after which it works fine. It mostly does this when first accelerating in the early gears, but it also does this when switching to the last gear sometimes. The Trans program will pop up on the OBC, and the acceleration would die. It would not accelerate at all (not like the typical trans program message); until i restart. So my question is, do you think it could be just a sensor or a bad transmission? Hopefully not the transmission since I recently just paid for a new catalytic converter which put me back $1800. I'm really getting tired of these problems. It's looking more and more like I'm going to have to end up getting rid of it. Hope not though

P.S A while back, a mechanic said the transmission mounts were cracked, could that be the problem here?