Ok, pulled truck in the garage, speedo working but honestly not ready correctly. cut off the main power at the battery I always run a disconnect. And then after a 10-minute wait pulled the stock ECM
used Jeffs's fantastic wiring diagram and 0411 ECM he programmed for me with my tire size and other motor info (stock 5.7 Vortec) got it all wired up ran a little rich, Jeff reminded me to do my EGR wire mod and yep that solved that.
But no speedo, pulled the wiring and double-checked the VSS wires all good, speed reads on two different scan tools correctly when you drive so I know the signal is getting from the VSS (yes tried a new AC Delco one) to the ECM.
Tried two known good Air core motors no dice, tried a complete cluster again no dice. I have all other gauges working perfectly but no speedo
Any clues about where to look?
used Jeffs's fantastic wiring diagram and 0411 ECM he programmed for me with my tire size and other motor info (stock 5.7 Vortec) got it all wired up ran a little rich, Jeff reminded me to do my EGR wire mod and yep that solved that.
But no speedo, pulled the wiring and double-checked the VSS wires all good, speed reads on two different scan tools correctly when you drive so I know the signal is getting from the VSS (yes tried a new AC Delco one) to the ECM.
Tried two known good Air core motors no dice, tried a complete cluster again no dice. I have all other gauges working perfectly but no speedo
Any clues about where to look?
