A recent sweep of New Jersey gas stations by state and local inspectors resulted in over a third of them receiving citations for posting the wrong gas prices on road signs, changing the price of gas too often, and other other violations. The New Jersey Star Ledger made a very helpful map of the violator stations, available inside.
New Jersey has 3,142 gas stations, according to the Star Ledger. Inspectors checked 1,023 of them, and issued citations to 350 owners. New Jersey’s Attorney General encouraged consumers to report any violations they come across. A larger version of the map can be viewed here.
(Thanks to Ryan!)