Pakistan collapsed spectacularly after being put in on an Edgbaston pitch offering swing and seam movement, with the top seven dismissed in the space of 59 runs following a 43-run opening partnership.
Younis Khan, the one batsman to knuckle down, top-scored with 47.
No other batsman got to 20, with the second-best contribution coming from 24 extras.
England's best bowler was off spinner Jamie Dalrymple, who took two for 13 off six overs while Paul Collingwood took two for 23 in his 100th One-day international.
Pakistan lead the series 2-1.
England, who lost their previous One-day series 5-1 in India and 5-0 at home against Sri Lanka, kept the contest alive on Friday by winning at Trent Bridge.
The drama began in the 13th over, three wickets falling in successive overs at a cost of eight runs.
Imran Farhat, living dangerously as the ball darted about, went first, dawdling fatally before being brilliantly run out by wicketkeeper Chris Read.
The left-handed opener bottom-edged a cut and set off out for a run only for Read to scamper up and flick the ball through his legs and into the stumps before Farhat could get back.
Shahid Afridi, promoted as a pinch-hitter, then slogged across the line and was bowled by seamer Jon Lewis after making two and Mohammad Hafeez, on 18, played on after being beaten for pace by Sajid Mahmood.
That made it 51 for three in the 15th over and put huge pressure on Pakistan's powerful middle order. Mohammad Yousuf, however, got away with a top-edged six over fine leg off Mahmood before edging the same bowler to slip where Andrew Strauss tumbled right for a good catch.
Younis survived two scares, clipping Collingwood's fingertips with a return drive and then edging Mahmood only for the umpires to rule the ball had bounced just short of Read's gloves. One ball later, however, it was 72 for five as Collingwood nipped one back off the seam and got Inzamam lbw for two in the 24th over.
Abdul Razzaq had specialised in spectacular boundaries at Trent Bridge. There, he had hammered five sixes and a four off the final two overs of the innings. Here, he was bowled by a nip-backer from Collingwood with five runs to his name.
That gave Collingwood his 50th One-day international wicket and left the touring side floundering on 91 for six.
Just 30 runs came off the last 10 overs. Dalrymple got the wicket that mattered, Younis ninth man out.