Wire from engine to chassis?, identify this wire. Options

[spy00005]

hey i've been searching the forum but cant seem to find anything on this wire. im thinking its just a simple ground but want to confirm. and if is just ground im going to replace. the wire seems kinda torn up for some reason and it goes from the block to was seems like the chassis on the passenger side near the abs. i have the wiring diagram but can't figure out which this wire goes with. any help would be much appreciated. (also i see it has a plug in the middle but wondering if i can just replace it with a continues wire i have some 4ga cable i just bought)
its the one im holding


can see it starts on the block behind the hook. then its a lil shredded to a plug and continues to the pass side behind the abs lines it ends.

[spy00005]

well the battery is less than a year old (not that it couldn't have gone bad) so im pretty sure its fine. the big wire going to the transmission is the next ground im going to replace if this one doesn't do the trick. im going to double check the code im getting tomorrow i think it was 13 but i can't recall at the moment. and i think i replaced my distributor to see if that would stop the code. i'll make sure tomorrow though. thanks for all the tips i'll go through them and see which one gets rid of the check engine light.

what im getting is a code 12

12-

No "G", "G1", "G2" or "NE" Ignition Signal
To ECM Within 2 Seconds After Engine Is
Cranked, No "G" Ignition Signal To ECM For
3 Seconds With Engine Speed Of 600-4000
RPM Open In "G-" Circuit

This post has been edited by spy00005: Apr 30, 2012 - 9:18 PM