Sputtering/dying

My 92 300zx seems to have an intermittent problem with sputtering. At first it only happened in the rain when I was driving 45+ mph. I drove it in the rain one day and I guess I drove through a puddle that was about 4in deep, but I was driving very slow, and it actually sputtered and died. The electrical system is working fine. We took a look and saw that my air intake filter had fallen off and put it back on. The car ran fine after that, but after a few days started having the same sputtering issue. The engine also smelled like someone was barbecuing. I haven't had it checked, but I think my fuel pressure is fine, when I take the cap off there is a hissing sound as if it is very pressurized. Before I started having this issue the engine smelled like gas a little, I am not sure if that is related. I have been told to check the maf. It seems to have more issue when I accelerate than under idle. Is there anything else I should be checking?