A cute backheel from Andy Monkhouse after 43 minutes put Evan Horwood in the clear down the left channel and the full-back's cross was deftly hooked into the net by McSweeney.
Huddersfield could have gone second in the table with a win but struggled to get going against a disciplined Hartlepool side. And when the Terriers did get going they found on-loan Blackburn keeper Jake Kean in fine form.
The youngster dived at the feet of Gary Roberts after 26 minutes and also raced out to deny substitute Benik Afobe an equaliser late on. He also brilliantly turned away shots from Peter Clarke and Anthony Pilkington after Huddersfield had switched to three up front in search of a goal.
Hartlepool could have won by more, with Huddersfield keeper Alex Smithies doing well to tip away Steve Haslam's dipping drive.
Fellow substitute Colin Larkin also missed a sitter late on, blazing over the bar from close range when left unmarked at the far post from Horwood's cross.