did heads cam mods in sig.

i know of 2 thing that could be causing this.

1. there is a ground wire coming out of the wiring harness to the starter. the ground that grounds at the oil pan. i was cut in half and i need to fix it. in this harness there are 3 wires. purplish brown wire, power to the starter, and this ground wire. WHAT DOES THE THIN BLACK 16-18 GAUGE WIRE GROUND?

2. i broke the temp sensor in the driver side head, right below the exhaust ports. i replaced it with an auto zone part. the original had one green wire hooked into it. the replacement had a yellow and a black. AS OF NOW THE YELLOW IS HOOKED UP AND THE BLACK IS HOOKED TO NOTHING. IS THIS A GROUND?

thanks in advance, critter

 

also knock disabled, vats disabled

 

The black/white ground in the starter harness grounds to a lug that is on the block, just below the #6 plug. It is a ground for sensors and the PCM.

Sounds like you got the wrong sensor for the head. You need the correct one. You might try grounding the black wire and seeing if that might work for you.