Specs 2010 Chevy Cobalt, 2-door Coupe, 2.2LT Engine. 76k Miles.
Notes It has been a while since I've had a tune up, so I imagine I'm not doing my best to maintain good fluid levels. Checked all recalls and appears every recall was accounted for from GM (Not first owner, bought from Private Party)

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Situation
Around 10/8/22 I had an issue with my Cobalt. I drove it fine the night before, and the next morning otw to work, I experienced the following issues:

1. Not going into gear. It will go up to 1st then maybe up to 1.5 - 2 max. But it doesn't feel like I'm going anywhere near 2nd or 3rd gear.
2. Speedometer not moving beyond 0 mph (Max Speed, maybe 15mpg, like limp mode)
3. No handling. Power Steering feels very, very loose.
4. Power Steering on Dash

After seeing the Power Steering Message on the dash and brought it to the closest mechanic that had 5m to spare, to hook it up to the code reader and help me diagnose the issue. He came up with a bad speed sensor reading, but mentioned they could do try it as a first fix, but it might not be the problem. Not sure of the code he found.

I've looked at several YouTube videos since to try and fix the issues myself. From adding a ground to the TCM / ECM, to replacing the TCM, to making sure wires were not exposed due to engine heat. I bought a new speed sensor and will try that next, but before I keep going down the rabbit hole, I want to bring my issues here to try and get some assistance from the community.

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Changelog

• 10/8/22 - Power Steering Message on Dashboard Display
• 10/9/22 - Added a ground wire to TCM - no change in power steering / speedometer / transmission engaging issue.
• 10/11/22 - Ordered new TCM, and checked near coolant area for wires that may be too close and wiring is exposed, but didn't find any issues, it was already Zip tied away from the engine heat.
• 10/18/22 - Added a different ground wire to TCM - no change.
• 10/18/22 - Installed a new TCM - no change.
• 10/18/22 - Added the new ground wire to the new TCM - no change.

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Q/A
Generally, the entire wiring harness looks like a complete mess. For the wires that were outside of the disintegrating plastic covering/harness, and near the engine I wrapped with Electrical tape.
Did notice that there was a wire that appeared to be cut/broken. It looks like it's connected to the Speed Sensor and then appears to be a break. Would it be a big issue if it is cut?
Wires -> Speed Sensor -> Wire(cut/break)

See Images below.

1. https://imgeasy.com/images/cb8ded1f3...1b4f768cf0.jpg
2. https://imgeasy.com/images/85d31f8cd...f4bcd7c695.jpg
3. https://imgeasy.com/images/736e92dc1...bf006f8953.jpg
4. https://imgeasy.com/images/cf2433f74...2b4f01efc3.jpg
5. https://imgeasy.com/images/57479a75e...39da25b7db.jpg

• Please let me know if there is any more information I can provide to help you, help me.

Thanks for your assistance,
Cobalt Issues

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Tags:
cobalt lt, Speedometer, power steering, not going into gear, 2010 Chevy Cobalt, 2.2lt

 

Update, speed sensor {might be fine}, but the plug + wire that connects into the speed sensor is disconnected from the wiring harness; which is causing the speedometer (0mph, not moving) / power steering dash mess and no handling / car not going into gear.

Either something chewed through it, or they're just terrible wires {that got melted off by a hot engine, or small animal} - thanks Chevy.

Part that is connects into the speed sensor, with wiring severed:
https://www.partsgeek.com/tnhnm9b-ch...connector.html