I've search this forum but have not found a complete answer . I have an early HP tuner (not the pro) without a side port in the interface to hook up the wideband thru. If I abandon my E.G.R. or AC temporarily & use there 0 to 5v signal that communicates thru the OBDII port , will this work. P.S. I did try asking the the chiefs at HP tuner, but did not get much of an answer! maybe he wants me to buy the pro series. oh, 03 silverado set up. thanks