Im assuming its a ground problem but let me know what you all think and post potential fixes.

every once in a while the temp guage will not work, or it will flicker at the speed of the motor. Drive fast the faster the flicker. slow down it gets slower. But if i go over a bump it sometimes makes the guage work perfectly? Any suggestion on what to check?

second, my passenger side power window stopped working. I know its not the switch because the driver side works and i swapped them and it stilled work. It worked before the winter and now it doesnt.

lastly, my gas guage. It will hang up on F for the longest time untill either i get really low on gas or go around a turn or hit the brakes. I did have a problem with the gas cap last year, it wasnt venting and built up a lot of pressure. when i discovered this i repalced the gas cap and ever since the guage hasnt worked properly.
any suggestions?

these are weird issues and i have a funny feeling that they all might be related. Let me know what you all think and help me out. thanks!