2004 Jeep Grand Cherokee, 4 ltr. 4WD

jeep
engines
cherokee

#1

While going up a steep grade, engine starts to skip/sputter and check engine light comes on. Shut the car down for 2 minutes, runs okay but light stays on. 1st time it happened, mechanic replaced spark plugs, coil pack and filter. Has happened again, and mechanic’s computer says #3 cylinder misfired. Has anyone else had this problem, and if so do you know what the fix is?