Shaun
I'm Awesome
I finally got my swap done. I had a harness modded for my truck. everything single thing is working, except the Tach gauge. from what i understand, the OBS tach cluster reads a 8 cylinder signal, and the 5.3 pcm reads a 4 cylinder signal. When i had my harness modified, and my pcm tuned, the harness had wires labelled for the dash (SES, speedo, tach) and the pcm was tuned for the older tach to read correctly. The Tach isnt reading ANYTHING. not even an incorrect reading. it doesnt move, period. My speedo is dead on, and all the other gauges are working as they should. I ended up cutting the ground to the fuel pump / fuel gauge sending unit where it comes out of the fire wall on the drivers side (also where i tapped the new fuel pump relay into the gray wire), and put a hoop connector on the wire, and grounded it to the body. I did this because the fuel gauge wasnt working. now its working great. My question is, is there a ground that is only for the tach, and thats why it isnt working? Or do i need this resistor, or whatever it is that corrects the signal? from what i understand, it should just work because the PCM was tuned for it. i'm not stressing too hard, since everything else is working perfectly. but i'd like to get it to work. all the other gauges, and all the back lights work fine. and i'd like to know if theres something i'm missing before i tear the dash back down to see if the wire came loose or something. Not sure if anyone else has ran into this problem. i keep searching, but it seems like most people are having problems with other gauges. My tach doesnt even twitch. no movement whatsoever. Thanks in advance guys!
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