The traverse has suspension components in the rear on each side that are attached using rubber bushings. When these bushings begin to wear the car will shift to one side or the other. When travelling straight down the road the smallest steering motion will cause the momentum of the car to shift directions, effectively pulling the car to one side or the other. As the driver attempts to counter steer to correct this shift, the car will shift back the other direction. Because the bushings arent tight this back and forth motion causes the wobble you are describing. I beleive there is three components on each side that are rubber mounted that join the cars chassis to the wheel assembly, and by jacking the vehicle up and using a prybar, you can usually see the sloppy movement easily.
https://www.engine-codes.com/p1621.html
This site has several possibilities including low voltage to the electrical system causing various drivability problems.
take the air temp sensor off. and leave in warm house. till at your homes warm temp then go out and install the sensor.and start engine. if it starts this is your problem.
DTC P0717: Input Speed Sensor Circuit Low Voltage
If you don't know anything about automotive electronic's , sensor electrical circuit's ,your best bet would be to take your vehicle to a qualified repair shop.
Finding a wiring diagram ,reading how this sensor work's an testing the electrical circuit using a DVOM - digital volt ohm meter , going by a factory service repair manual .
Diagnostic Fault Information
Circuit/System Description
The input speed sensor (ISS) is a hall-effect type sensor. The sensor faces the 1-2-3-4 and 3-5-R clutch housing machined teeth surface. The sensor receives 8.3-9.3 volts on the input/output speed sensor (ISS/OSS) supply voltage circuit from the transmission control module (TCM). As the 1-2-3-4 and 3-5-R clutch housing rotates, the sensor produces a signal frequency based on the machined surface of the 1-2-3-4 and 3-5-R clutch housing. This signal is transmitted through the ISS signal circuit to the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly uses the ISS signal to determine line pressure, transmission shift patterns, torque converter clutch (TCC) slip speed and gear ratio.
Circuit/System Verification
Engine idling, observe the scan tool Transmission ISS parameter while varying the engine speed. The Transmission ISS parameter should change with the engine speed and not drop out.
Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Your best bet ,take it to a qualified repair shop.
I spent hours in engine and on the internet. I viewed 15 different sites with 15 different answers. Finally found it...The crankshaft position sensor on a 2009 Chevy Traverse (3.6 liter) is as follows: You need to jack up vehicle (or useramps) and climb under. You CANNOT access it from top (as many sites state). On the firewall (vehicle) side of motor, in the center, directly below the exhaust outlet, you will see a silver (aluminum) heat cover/plate. It is held on by 2 bolts. (one 15mm and one 10mm). The sensor is located benind this cover. Once you get this cover off, you will see two seperate sets of wires, wrapped in silver heat deflection tape. The set of wires that extends further to the left go to th CPS (sensor). I used a small extendable automotive mirror to see it. It is in a tight spot, but once you find it, it is easier to access than it looks!!! Took me about 30 minutes total to switch it out. Hope this helps !!! Good luck.
Most likely is fuel filter; if it does it with a new fuel filter check fuel pressure at engine at speed it looses power--maybe the fuel pump is laying down.
OK. you had the battery disconnected. Here is what you do. Turn on the key. The security light will begin to flash. Wait (about 10 minutes) with the key in the ON position. The security light will stop flashing. TURN OFF the key. Then, turn on the key and start the car. Security system is supposed to prevent theft for a 10 minute delay. This usually discourages any thief. This will work, You just need to be patient with the 10 minutes. It seems like an hour when you wait ten minutes for that security light to stop flashing.