The North End No.9 rose highest in the box to meet a superb cross from the returning Lee Holmes to head into the bottom left hand corner in the fourth minute of stoppage time.
Hoe Garner had given the visitors a first half lead after he slotted home a penalty after getting up and dusting himself down following referee Richard Clark’s decision that Steve Simonsen had brought down the on loan Watford man.
Manager Graham Westley had gone into the game making two enforced changes; the injured Shane Cansdell-Sherriff and suspended Jeffrey Monakana replaced by the returning Bailey Wright and Saturday’s goalscorer David Amoo.
And it could have been another blistering start from the Lilywhites as Scott Laird’s fourth minute corner was met by Chris Robertson, but a defender did brilliantly to flick over bar. However, from Laird’s second inswinger, the No.3’s cross appeared to have gone straight in, however, the referee and his linesman said it hadn’t crossed the line.
The half was from that point a very scrappy affair, with PNE trying to get ball wide and the visitors happy to sit in with ten behind the ball and try and frustrate and these tactics paid dividends when Garner latched onto a short back header and North End keeper Steve Simonsen was adjudged to have brought down Joe Garner on left edge of box.
There was a big delay between the decision being given and the penalty being taken, but the Carlisle man stayed calm and sent the PNE custodian the wrong way, sliding the ball into the net to the keeper’s left.
The manager introduced Lee Holmes at the interval, replacing Bailey Wright, with Scott Laird reverting to left back.
And on the hour mark Sodje was also added to the attacking force, with David Amoo withdrawn and with his first touch the frontman was inches away from levelling matters, powering a header from a Nicky Wroe free kick just over the cross bar.
North End from that point peppered the visitors box with balls, Chantler clearing off the line and Beavon firing over all within seconds of each other.
The visitors did all they could to run down the clock and waste time, much to the frustration of the North End players, officials and the crowd,
With 15 minutes left Nicky Wroe's 25 yard effort was just tipped over by Collin, with the corner by the same man punched off the line by the keeper.
Moments later a real moment of controversy as the goalkeeper handled the ball outside the box to get it away from Akpo Sodje yet somehow the referee gave the foul against Sodje, much to the home fans, players and management's disbelief.
Graham Cummins was thrown on to replace Jack King with 11 minutes left with North End throwing everything forward to try and grab, at the very least, an equaliser.
Four minutes were added to the play, and as the final minute began Lee Holmes showed the quality that the side had been missing with a sumptuous cross from the left that saw Cummins rise highest on the penalty spot to head down, past the outstretched arm of Collin and into the bottom left hand corner to grab a point for the Lilywhites.
PNE Line-Up: Simonsen, Keane, Wright (Holmes, 46), Wroe, Huntington, Robertson, Amoo (Sodje, 60), Byrom, Beavon, King (Cummins, 79), Laird. Subs not used: Stuckmann, Procter, Beardsley, Hayhurst.
Carlisle United Line-Up: Collin, Simek, McGovern, Murphy, Noble, Edwards, Potts, Berrett, Garner, Chantler, Higginbotham. Subs not used: Welsh, Cadamarteri, Todd, Symington, Gillespie, McGinty, Bugno.
Referee: Mr R Clark
Attendance: 9,249 (941 away fans)