[rfmaster]

Originally Posted by el phantasmo

Great thread guys! Maybe too great b/c I have accumulated all the parts and pieces need for a tbi swap of my own. I have done my homework and I think I have a decent grasp of what I need and what to do with it. But I do have a couple of questions and I know you guys have the answers. I think my harness came out of a 1990 van don't know if it was a 5.0 or 5.7 or what ecm #. The ecm I have is a 1227747 AMUR from a 1988 c15 w/5.7. My harness matches the pin out cjracing15's in post #8, except for two wires are swithced. D2 is purple and goes to the MAP sensor and A11 is black and goes to the coolant temp sensor. My harness matches rfmaster's diagram in post #108. Should I swap the wires? My other question is VSS related. Would a universal cruise control speed sensor work? Sorry for the length and thanks for the thread it rocks!

No problem on the length. Your ECM with AMUR BBC calibration was used in 1988 C/K 1500 with a 350 TBI/700r4 combo. Generally speaking wire colors used in GM EFI harness remained more or less the same. What's really important what those wires connect, ie sensor <-> ECM.

ECM D2 is a sensor ground - I have seen various colors used for this circuit, but truck based harnesses tend to use black with red stripe.

ECM A11 is another sensor ground and can be either black or purple. This sensor ground does not connect to the temperature sensor itself, but it uses a thermostat stud for a ground connection.

//RF