Cold start problem!!!
i have a 2000 audi tt 3 months ago i swapped the engine with one from a 2004 jetta the only difference between them is vvt mine did not have it the jetta does. since i replaced the engine ive been having cold start problems like rough idle, multiple cylinder misfires and even engine shut off every now and then but if the engine shuts off the car will not start back up it will just crank slowly like if there was no spark and if it was flooded with gas. i really really need help with this its driving me insane idk what to do i replaced plugs, coils, coolant temp sensor, maf sensor and nothing has changed i also have an overboost issue idk if the two are related or not codes are cyl, 2 3 4 and random misfire and turbo bypass valve open. please if anyone has any ideas i will greatly appreciate them.