no start issue

[JohhnyFoxtrot]

Have a truck here that did run on 3 cylinders changed an ecm then back to original ecm and now it won't start at all. Checked resistance on injectors all came out at .038-.040 except #6 which was way high. I unhooked it and now it still wont start. Fuel pump works cp3 makes pressure will start on starting fluid but won't run when its gone. Truck is an '05 not sure what else to check or do. Any ideas to check is welcome.

Thanks

 

[XLR8R]

Make sure the dedicated ECM ground to the driver's fender ground bolt is connected.

 

[Heimz]

More than likely a ground, I had the same issue this weekend when I pulled my neg's off the batt's for electrical work. I put the grounds back on, but didnt tighten them. I would get the stereo and lights and everything else but truck wouldnt fire no matter how long I cranked it over. My DTC reader couldnt communicate to the ECM, so it wouldnt tell me the code i was throwing. Tightened the battery terminals and it fired right up, then had to clear the DTC code P2509.