2001 Ram 1500 starting HELP!!!!!

[2001dodgeram5.9]

Hi I am curious if anyone out there has a 2001 ram 1500 5.9 sport/offroad. My MIL is on and I cant access the codes, my scanner says linking error. So I bought a new better one (autoxray ax6000) emailed the company to confirm it would work on my rig and even bought the chrysler enhanced cable and what do I get? a "vehicle is not responding" message. Has anyone out there with this exact rig been able to successfullly retreive codes with the DRB $7000 scan tool? She was running fine yesterday and only has 67k on her go to start it up today and she wont run without my foot on the gas and as soon as I let off it dies instanty, if i hold the throttle at any position it will idle then rpms will drop suddenly about every 1/2 to 1 second also the check guages light is on and the fuel guage is not working at first I thought someone siphoned my gas but I put 10 gallons in and still nothing sorry for the lengthy message but I NEED HELP!!! Thank you!!!!