P0171 and engine stalling

2003 2rzfe 2.4l, 2wd m/t
I'm having trouble figuring out what is causing my lean code. When I apply the gas, it tries to stall. It revs back up when I raise the pedal. Could this be improper install of the tps?
It also bogs down when I apply the brakes, but I don't know if that is a separate issue or not...
Any help is greatly appreciated.

 

Was the tps replaced recently? How do vacuum lines look? Brake booster good? Sounds like vacuum issue. I would start with easiest stuff. Check for any vacuum leaks, check fuel pressure, then maf sensor. try cleaning it with maf cleaner.

 

It's was the gasket around the master cylinder piston

 

I was wondering if that served any kind of purpose. About to do my booster and master, i better get a new gasket.....