Hey guys, I just bought a 04 cavalier, and it has a couple problems the main one being a sudden sputter to dead. Also gas gage doesn't work and temp gage as well. wondering if problems are connected or not?

 

Update: So the check engine light was on but the alarm wouldn't stop going off so I disconnected the battery and the check light went off. Then I took off the intake tube and it seemed to run better but still runs ruff when slowing at a stop light. Also new problem, I noticed that it shifts hard into every gear weather I am hard on the throttle or not. Any suggestions?? Thanks in advance.