Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I know I'm a new guy but I worked on these everyday for more years than I care to admit. Will it run and stay running if you feed if fuel like a flammable brake clean? What is your fuel pump amperage? If you crank the truck for 3 seconds will it stay running? Lots of problems with ignition switches, is the ignition voltage stable? Does the theft deterrent light actually come on during a bulb test? I had one that someone put diesel fuel in and it acted the very same way. did you do a fuel quality test. I usually just pour a bit on to a metal work bench and see if it evaporates. If it doesn't, you've got problems. I only ask because I didn't see any of the basics covered.
Hello, let me update everyone on this issue I'm having. I went to lkq picked up a passlock sensor ($20 Bucks) installed it and it turns on bit now I get a security light that comes on after a few minutes. I will post the code later I forgot what it was. What I did notice is that now the reading goes from 5v to 3.3v unlike before when it wouldn't start so now it does get pulled down amd it starts. After driving for a few minutes the security light comes on and the 3.3V goes back to 5v. It also reads "open" instead of "Valid code 7" on the scan tool parameters.
