Re: ITB Conversion on 16 valve 4AGE On my inventory bigport AW11 a leaking exhaust manifold gasket caused the O2 sensor to read lean and it pumped fuel into the motor. Fuel economy plummeted until I sorted it out. Unplug stock harness from all engine-sensors and components like injectors and https://nathanielg913jkm7.blogsumer.com/33787835/top-latest-five-toyota-4a-ge-urban-news