My nephew has a 98 F-150 filling up gas at station & noticed gas spewing out under the truck before it was full. Figured it was just overflow... We get home & he tells me his check engine light had been on all weak. Code reader gives P0301 cylinder 3 & 5 misfire. I replaced #3 & #5 sparkplugs. Check engine light came back on flashing. P0301 again. Now with cylinder 3, 4 & 5 misfire. He noticed gas leaking again when he drove from driveway to garage behide our house. His mom added fuel system cleaner to gas because someone told her fuel injectors can cause P0301 & if cleaner didnt help then fuel injectors were bad & needed replaced.... I figured plugwires or bad coil pack until I heard about gas leaking again, this time in driveway.
?????
Anyone have any experience with this sort of problem? Or P0301 Fod F150 1998.
It wasn't sparkplugs

 

Should be fairly easy to find out where the gas is leaking from if they look. It could be dangerous. Insist they get on it right away.