I have a 2004 5.3L in a 58 Chevypickup. I got the engine running about a week ago but I am not getting a MAP signal. Does anyone out there have the pinouts for a 2004 computer so I can eliminate a wiring problem? Thanks Mark

 

pin 48 connector 1, gray, 5 volt ref. to pin C on map sensor
pin 54 connector 1, orange/black, low ref. to pin A on map sensor
pin 32 connector 2, lt. green, map signal to pin B on map sensor

 

I found almost the same info on a 2002 pcm, except for the 54 terminal was blk. I suspected that they only changed the wire color in 2004 and you confirmed it. The person who wired this harness used the wrong pins. Thanks for the info Mark