Reply to thread

Message: [QUOTE="Patrick Feeley, post: 227036, member: 2142"] I harp on this all the time: If you're going to keep your truck (or do a bunch of work such as this), buy the Electrical and Vacuum Troubleshooting Manuals (EVTM)!!!!! Best money you will ever spend! Just looking at the diagrams (I have all the EVTMs from 94 through 97) here is a description of differences between them (NOTE: only the TPS described below!): [B][I][U]1994:[/U][/I][/B] Reference Out Voltage is on circuit 351 (BR/W). This wire is from connector to PCM pin 90 (and also goes to the BARO, MAP, CPS, EBP, and ICP). Sensor Signal Return is on circuit 359 (GY/R). This wire is from connector to PCM pin 91 (and also goes to BARO, MAP, IAT, EOT, EBP, ICP, and pin 2 on the IDM). The TPS "tap" is on circuit 355 (GY/W). This wire is from connector to PCM pin 89. [B][I][U]1997:[/U][/I][/B] Reference Out Voltage is on circuit 351 (BR/W). This wire is from connector to PCM pin 90 (and also goes to the BARO, MAP, CPS, EBP, and ICP). [B][I][U](so really no difference there)[/U][/I][/B] Sensor Signal Return is on circuit 359 (GY/R). This wire is from PCM pin 91 to all of the following: BARO, MAP, IAT, EOT, EBP, ICP, and pin 2 on the IDM. [B][I][U]It does not go to the TPS![/U][/I][/B] The circuit 570 (BK/W) wire on the 97 TPS connector needs to get spliced into the circuit 359 (GY/R) wire for the sensors listed above in this paragraph to be consistent with 95 PCM wiring). On a 97, circuit 570 (BK/W, a ground) wire would go to PCM pin 24 (that pin is not used on earlier trucks). The TPS "tap" is on circuit 355 (GY/W). This wire is from connector to PCM pin 89. [B][I][U](so really no difference there)[/U][/I][/B] Now as far as other differences, there looks to be some other differences at C202 (big harness firewall feedthrough connector). Probably not a lot of help. Cheers! [/QUOTE]