My '92 Max SE had been running oddly for last 6 months. It started up OK, but not long after I drove, it would hesitate, feel like it was running out of gas, stall out at various speeds, sometimes smell of gas. Condition never got worse, just ran rough. Changed the plugs, air filter, gas filter. Put fuel injector cleaner in the tank. No fix. At various times, I hypothesized it was a fuel injector, then a gas line filter, a gas tank filter, a head gasket problem, a thermostat, a gas line leak. I expected the solution to include big bucks. I was at wit's end.
Today, while driving, I rationalized that it might just be that the pressure in the fuel lines that is not being maintained or I had a pressure leak. What if it was the gas cap that caused the pressure to give out? I barely remembered having to change a pressurized gas cap because the old one had lost a good seal. So I bought a new one, and immediately, my car got back to the smooth driving I had almost forgotten! Man do I feel blessed!
Moral - remember to change the gas cap!