1994 Toyota 4Runner

We just put a new motor in my 4runner at about 200,000 miles, and alot of new parts in it but at about 5,000 miles the idle on the motor started acting up. We check the mass airsensor, the distributor, did a compression check on the motor, changed a few fuel injectors, put new spark plugs. The check engine light came on and code comes up as 26 stating that the motor is running rich.