Oil is one component of the price of gasoline. The other big components are refining costs, distribution and taxes. The oil companies don't control the last one so let's look at the other two.
Refining costs - we been maxing out at refining capacity for years. Add to that, changes in regulations both longterm (reduction of MTBE) and short-term (switching between summer and winter blends). Any interuptions in refining capacity directly impact supply. Look back at this summer and you'll see the impacts of both.
Distribution costs - there were several supply interruptions and pipeline problems. Add to that, the fact that ethanol product must be trucked/tanked rather than pipelined.
Oil lag. Finally, there is a lag effect with oil price swings. Essentially, buyers are looking at replacement costs. When prices go up, buyers look to hedge on replacement. When they go down, they are pricing based on what they paid.
Finally, no evidence of gouging exists. It is investigated nearly every year and no evidence is ever found. Profit margins are relatively low and stable. Gouging would show up in margins - it is not there. Oil companies are profitable because they have a relatively low and stable profit margin on huge volume of product. As demand increases, profits do as well. Simple math.