also while the back wheels are off the ground, crank it up and put it in every gear slowly like you are driving normal because if it jerks to hard the car is going to come off the jackstands
i understand what your saying, and i dont think pulling codes will help, its not a prob with your motor, it is in how you drive it, but bfor you get all defensive, im not saying your a bad driver at all, im just sayin, with a stick, its VERY difficult to just pop the clutch and gas on it, your talking about having to have lightning quick reflexes to be able to get the gas to it bfor it dies, you said you used to do it all the time, but you can actually change the way you do it every time, whether you realize u r or not, if you dont do it with perfect timing, it will not work, next time, try to give it a few hundred rpm bfor you pop it, it might make all the difference in it takin off or boggin out, jus my $.02
one thing that helped was puting 10/40 oil in instead of 20/50 with lucas oil suplament. it didn't fix my problem but now on certain street the tires will brake loose when i lauch at idle. it could be a number of problems because my care was sitting for a couple months. i don't here any noise from the rear or anything like that. i thought about the slipping clutch idea because im starting to be able to here my throw out bearing sqeak, but i don't think it's the cluch because if that were the case my rpms should be shooting up while i go no were. So if nothing is slipping, my rearend isn't going out or my loose motor mount isn't affecting my launches then i think its an ignition or electrical problem. i do have a bad electrical system. my car turns over about 7 times and then it starts. and once it starts my voltage hangs right above the read line on my volt meter.then i have to rev up, once i reach about 1700-2000 rpm my volts pop back up to normal. if i don't rev up the car dies and has to be charged and it does that everytime i start the car. i know its not my battery because ive changed batterys and got a new aptima battery. so im thinking i should get a 3g alt.