i've recently swap a 91 ls motor into a ef, its has header, intake, exhaust, fuel gauge and regulator, the problem is that it seems to leak or burn alot of gas, i've lean out the car and it still wastes alot of gas, usaully 4-6 miles per gallon.. i've also check the gas lines, fuel pump, spark plugs, plug wires,.. i need help...

also it throwing a code 7 for the tps sensor and code 13 for pa sensor

 

check the o2 sensors, and you might have some dirty fuel injectors.