This listing is for a plug and play flex fuel harness for GMT800 or 900 trucks. The flex fuel sensor gets its power and ground from the coil pigtail and all that is needed is to pin the ecu. After ordering please specify 99-06 truck or 07-13 truck as the ecu pin changes. 

Our harnesses are hipot tested, sonic welded splices, crimps all done on calibrated manufacturing equipment. 
This harness is designed to be a plug and play solution for 99-13 Silverado and other GM trucks of the same generation. This does not include any fittings or sensor.