Brian,Frank, I must have really struck a nerve with that crc sales comment. I apologize. To Brian or Frank...would you replace the o2 senors first or the fuel pressure regulator? On the suggestion of the Gumout. I used Lucas Oil brand injector cleaner on the tank after i cleaned my maf, the truck is running great, idling great, just still the bad gas mileage???
To be honest with you, I would replace the cheapest and easiest to reach first. Unfortunately, the first may not always fix it. O2 sensor is generally cheapest (if not hot wired) and easiest to replace. I know this may sound a bit off, but have you checked other contributing factors that cause bad gas mileage? IE...underinflated tires, objects causing wind resistance, or even making sure that your brakes arent intermittenly hitting the rotor/drum (loose/worn calipers/springs can cause that). Im sure you have but you would be surprised at how many people overlook the small items. Taking off your tailgate (although usually looks unclean) saves on gas mileage too. I wouldnt worry too much about Frank, Im sure he is over the CRC comment. He seemed to get a good laugh out of it. Hope this helps, re-post if you uncover any new elements.