Hesitation help

I have a 99 tacoma prerunner, w/ 3.4 V6. I keep getting lean codes, and today my truck is hesitating bad. When it is cold it wont accelerate, i have to wait till it completely gets to operating temperature. Then i can some what drive it. The injectors were replaced last year, the fuel pump replaced 1 month ago, fuel filter replaced 3 weeks ago. My truck has a first gen trd supercharger on it. Can someone give me ideas on what it could be causing it to hesitate, it was running fine up till today. Thank you

 

Check the EGR valve isn't stuck open (or closed) Check vacuum lines for leaks. Just guesses. If the truck has over say 130k I'd seriously think about a new 02 sensor. Hell, try a new coolant temp sensor, too.