Strange issue with 1999 S70 NA after contactless TPS install

[Hoofbaby]

Hi everyone,

The ETS light has been on in my car for a while, and failing smog for pending code (ECM-9150: throttle position sensor 1 faulty signal) led me to ordering a contactless tps kit from eBay. With the help of this forum, it seemed easy enough. After I got the sensor replaced and all put back together, went to start the car and the idle shot up to 3000 rpm and stayed there for about 20 seconds. Then the idle would bounce between 2k-3.5k on the tach, and would just do this continuously. The ETS light was on the whole time and once the CEL engine light came on, I turned the car off. I reached out the the eBay seller and they told me that they had actually received a batch of unprogrammed sensors and we determined that I had in fact received one of those units. They sent out another contactless TPS, confirmed to be programmed for my s70. I take the back unit out and put the good unit in, get the throttle back in the car. Starts fine, idles high with a bit a hunting, but for the first time in a while that ETS light was gone— what a beautiful sight! The CEL was gone as well. I took the car for a drive, and within 5-6 blocks the car started idling erratically and entered limp mode. I put in a new battery just to make sure the signal was getting enough power. I cleared the codes, rescanned, and am now getting the following codes: p1033, p1028, p1027 (I believe throttle body related), and p0645. It’s worth noting that the ETS light and CEL are off (at least for now), but unfortunately a strange noise is happening. I've included a video of the noise— it's like a slowly increasing humming sound that's coming from somewhere in the engine bay?
I got in touch with Xemodex, and they suggested I send my throttle body to them for their repair and return service. I am planning on doing that, but just wanted to see if anyone here has idea what might be causing this. Thanks!