Brendos

I Have a 2006 hilux workmate with the 2tr fe engine that has a P0171 fault. System too lean bank 1. I have put the scan gauge on ant the pre cat and post cat sensors are reading 5v and .3 v . I think the pre cat sensor is an afr sensor and the post cat is a oxygen sensor. Is it right in assuming the pre cat reading at 5v is too lean. Could it just be faulty sensor or could it be something else. Vac seems very good . The fault is intermittent after clearing it. Does anyone know what commonly brings this fault up in these engines. Injectors ,coil packs etc. Thanks

I have a LN 167 with a 5LE I think it is running a bit rich and sooting slightly. Power seems ok and running ok I know it is electronically controlled but I have been told that there is a manual mixture screw as well. Does anyone know any thing about it and where It is and adjustment etc. Thanks