The lively Fijiians threatened to pull off a major upset when they led 6-0 but England hit their straps in the third quarter, scoring five tries in a devastating 15-minute spell to spare their blushes.
They will now play the losers of Monday's final Group B match between France and Samoa in the third quarter-final at Wigan next Saturday and, on the evidence of their second-half showing at the KC Stadium, will be supremely confident of at least reaching the last four.
They will need to play for the whole 80 minutes if they are to get past New Zealand in a likely semi-final but there were more encouraging signs for Steve McNamara's men.
Winger Ryan Hall, who went to the top of England's scoring charts with a hat-trick in last week's win over Ireland, scored two more to take his total to 19 from 18 appearances.
But England's hero was South Sydney forward Sam Burgess, who missed the Ireland game through suspension and showed his class on his return with a man-of-the-match performance that included the try that put his side in front for the first time.
England, who gave a debut to Wigan second rower Liam Farrell, had struggled to find much fluency in the first half and the Fiji defence proved resolute.
Sam Burgess went close to opening the scoring after Fiji loose forward Korbin Sims was put on report for a "spear" tackle on James Graham but he lost the ball in Ashton Sims' tackle as he stretched out for the line.
England had a let-off on 22 minutes when centre Daryl Millard got to the ball from Aaron Groom's grubber kick on the last tackle but referee Ben Cummins went to video official Shayne Hayne and he disallowed the try for an obstruction in the build-up.
England had plenty of possession, courtesy of a first-half 7-3 penalty count, but the Fijiians were far from over-awed and they took the lead on 32 minutes when second rower Tariq Sims burst through a stretched England defence and got substitute Eloni Vunakece over for the game's first try.
Wes Naiqama added the conversion to make it 6-0 but England drew level three minutes before the break when substitute Westwood supported a half-break by Sinfield to cross for a try, which the skipper goaled.
England suddenly clicked into gear at the start of the second half, prompted largely by Sam Burgess, who scored within 25 seconds of the re-start.
He collected the ball from Sinfield's kick-off after the Fijiians allowed the ball to bounce and two tackles later proved unstoppable from 10 metres out.
That put a spring into England's step and stand-off Rangi Chase came into his own to help create two further tries to enable his side to seize control of the match.
Chase's delayed pass for second rower Ferres over and five minutes later he freed Hall, who produced a tremendous trademark finish for his first try of the match.
Sinfield received a blow to the head early in the second half but eventually got to his feet and showed no ill-effects as he converted both tries to make it 24-6.
England looked sharper following the introduction of Burrow and he added a try on 52 minutes following a break by George Burgess, with Sinfield kicking his fifth goal.
Fiji could not get their hands on the ball at that stage and they conceded again when Tomkins chimed into the attack to put Hall away for his second try to stretch his side's lead to 34-6 after an hour.
England went quiet after their purple patch as Fiji finally got their hands on the ball to pose more problems for their hosts.
Sam Burgess was brought off for a deserved rest after 61 minutes and, after Briscoe was denied a try for a forward pass, it was the Fijiians who enjoyed the better of the final quarter.
Their enterprise was rewarded when right winger Semi Radradra produced an impressive finish for their second try and Naiqama kicked his second goal to wrap up the scoring.