Dodge v10

First suspect a misfire, as in spark plug or wire. A misfire will send unburned gas and air into the exhaust where the unburned oxygen will be detected by the O2 sensor. That means the Engine Computer will add more fuel to all cylinders on that side of the engine. No matter how much fuel it adds there will still be that unburned oxygen in the exhaust so it keeps adding more and more fuel.

If there's a lot of black smoke from both sides, (if you have dual exhaust), suspect a failing MAP sensor. He has the biggest say in how much fuel is needed.