Ok so i have a 97 eagle talon tsi and i just put a bigger turbo and an inter cooler on it and it was running fine for about 2 days. Ok so here is the problem i can start the car and it will idle fine fine and i can rev it up to any rpm fine but after about 20 seconds of letting it even sit it seems to just wanna be retarded. After that short time period is up it will seem to go into like a safe mode it will idle fine but will not rev above 2000 rpm even while driving it wont go above 2000 rpm. also while it is at 2 grand if i try to go higher it will just seem to be like misfiring and will shoot black smoke out the exhaust and it will stay in this safe mode all the way till i turn the car back on .....   OOO and here is the kicker there is no check engine light on at all!!!!!!    i need some suggestions here i am going nuts  

have you changed your ECU? is your intake sensor connected correctly? have you checked your 02 sensor.  

also check the map sensor.
how much boost are you running?

btw its probaley not good to drive it like that.