Oil prices are at $30 a barrel, after falling below $28 a barrel.
The US and European Union lifted sanctions in Iran over the weekend. That means more oil on the market that could lower gas prices.
In Houghton Lake, Michigan, customers took advantage of a price war between two gas stations Sunday. One station dropped to 53-cents per gallon, so the competing station went to 49-cents per gallon.
Drivers loved the price, but they are back to the normal rate Tuesday.