After a ifixit battery change, CPU throttles and fans go crazy

hi everyone,

I replaced my battery after 8 years of using the macbook. everything seemed to work fine, and i was pretty confident that i didn't destroy any connectors while taking out the logic board and everything according to the repair manual.

well, after all it appears it did break something. others had this problem after a battery change as well, some fixed it by looking for loose connectors, but mine all look pretty well, as far as I can tell. Resignated I brought the Macbook into a Apple repairshop, but of course they denied even looking at it, after telling them that I had replaced something myself. I am a bit desperate now, as it was still running pretty well and I was hoping to use it for some more time. Now I am wondering if anyone here has an idea what I can try, because with the blocked CPU it is pretty much unusable.

TB Pro is reporting an issue with the hard drive temperature sensor, even though SSD1 and SSD2 temps look good to me. I noticed that the GPU has some very short 90C peaks, but then quickly returns to ~28C.

Anyone an idea what i can try, check or look at at this point, or a software way to block out the SMC throttling. I read there used to be options to do this, but don't seem so with newer macOS' (using Monterey), also I am not expirienced with any github things.

Thank you in advance!

Sebastian