If my cold side cobalt map sensor is effing up and I have the GM stage 1 map sensors. Can I use the old stock map sensor as a replacement or have to get another GM stage 1 Bosch sensor

 

Get a new stg1 sensor. I believe crate engine depot has them pretty cheap. Your cars flashed for those sensors, plus they won't work with the new harness.

 

Absolutely not! It's a completely different sensor with different scaling. You're car will most defeinitely go into limp mode if you attempt straight up swapping either of the GMS1 3bar maps, for the stock 2.5bar. You're just better off dealing with it for the time being and just order a new one.

You can even try cleaning the sensor in question with some electrical parts cleaner, or maf sensor cleaner and blowing it out with some compressed air and see if that fixes the issue

 

It could be the wiring. Be sure to check the solder joints for corrosion/wetness. If you don't have soldered joints, then it is definitely the wiring.

 

I ordered a new sensor and when I put the new one on ill check the wore and solder. Thanks for the advice guys