5 On Your Side on gas prices: The best - and worst - days to fill your tank

When gas prices seem to change every day, it’s tough to know when exactly you should fill your tank. As it turns out, there are days when gas is supposed to be cheaper.

According to GasBuddy, Sundays are the best days of the week to buy gas in North Carolina. The worst days are Wednesdays. 

This follows national trends, too. Research shows fueling up midweek, between Wednesday and Friday, is going to cost you more, as much as 4 to 9 cents per gallon. 

However, this cost-saving measure may need to be put on hold.

Matt McClain from GasBuddy told WRAL News that which day you buy gas doesn't matter right now due to the war in Iran. The war has disrupted oil supply so much that buying habits are in flux, McClain said.

"We have the volatility that takes, ‘Hey, buy gas on Tuesday,' and throw it out the window," McClain said. "Everyone is reacting to the additional stress in the crude oil market as a whole. There’s too much volatility for there to be a pattern.”

While holding out to buy gas on a specific day won't guarantee saving you money at the moment, there are other ways to conserve gas. 5 On Your Side has a list.