Switching IC via FTDI232 DTR and transistor
Maybe you connected the transistor the wrong way?

Instead of the ESP, insert a light resistive load R (e.g. 100 Ohms) between P4 and P2. Then switch this load on/off with DTR and check if the voltage at P2 is changing from 3.3V to 0V with a multimeter. 

Please also make sure that you provide some capacitance C to the ESP VCC input in the final design.