Kevin Kelsy gave Gers the lead in 16 minutes, before Hearts responded with goals from Claudio Braga and Calvin Miller.
In the final minute, Makhanya headed home his first goal for the club, to see a share of the points at Tynecastle.
There was one change from the weekend’s victory over St Johnstone, as Djeidi Gassama came back into the starting line-up to replace Badredine Bouanani who was named on the bench.
Rangers started with Ivor Pandur in goal behind Dujon Sterling, Emmanuel Fernandez, Olwethu Makhanya and James Penrice.
Dan Neil and Nico Raskin were in midfield, with Minsu Kim playing in a more advanced role alongside Djeidi Gassama, in support of strikers Ryan Naderi and Kevin Kelsy.
On the bench this evening are Liam Kelly, Kosta Nedeljkovic, Ben Godfrey, Tuur Rommens, Vanja Dragojevic, Tochi Chukwuani, Findlay Curtis, Badredine Bouanani and Bojan Miovski.
As expected, it was a lively start in what was McInnes’ first game in the dugout at Tynecastle since joining Rangers from Hearts.
Inside the opening 10 minutes, Minsu managed to find Raskin with a cross, but his header was blocked by a defender.
It was Rangers who took the lead with 16 minutes played and once again it was Ryan Naderi and Kevin Kelsy combining.
Kelsy won the ball back in a dangerous area, before finding his strike partner in the box. Naderi controlled it well, before squaring the return pass to Kelsy who finished low beyond Reus.
Rangers weren’t able to capitalise on that opening goal, with clear-cut chances few and far between in the first-half.
For Hearts, Braga had an effort gathered by Pandur, before Miller also tried from range with the Rangers number one on hand to deny as Gers went in at the break with the single goal advantage.
However, less than three minutes into the second-half, the home side had their equaliser from a set-piece. Miller delivered a cross into the box, which Fagan-Walcott headed across the face of goal, and Claudio Braga finished from close range.
The goal prompted an early change in the half for McInnes, as Badredine Bouanani came on in place of Djeidi Gassama.
Hearts had their tails up though, and took the lead with 57 minutes on the clock. It was Braga who drove the attack down the left, before his deflected shot fell for Miller who found the back of the net.
Bouanani forced a save from Reus as Rangers looked to get back in it as the winger got on the end of a Hearts clearance and looked to bend a left-footed strike beyond the goalkeeper but it was pushed wide.
Braga had another big chance, as he got beyond Emmanuel Fernandez before cutting into the box to send a right-footed shot towards goal but it was comfortably gathered by Pandur.
Dan Neil found space on the edge of the box as the game approached the final 10 minutes, and the midfielder curled a right-footed effort towards goal which Reus managed to save.
With 89 minutes played, Rangers got the equaliser from a set-piece. The free-kick was delivered into the box by Badredine Bouanani, and Olwethu Makhanya headed home his first goal for the club.
Rangers' attention now turns to Saturday's Premier Sports Cup semi-final against Aberdeen at Hampden.
Rangers: Pandur, Sterling, Fernandez, Makhanya, Penrice (Rommens, 63), Raskin, Neil (Chukwuani, 84), Minsu (Curtis, 83), Gassama (Bouanani, 53), Kelsy, Naderi (Miovski, 83).
Subs: Kelly, Nedeljkovic, Godfrey, Dragojevic.
Hearts: Reus, McCart, Miller (Wilson, 78), Braga (Williams, 78), McPake, Magnusson, Altena, Kerjota, Fagan-Walcott, Mato, Mendy (Kingsley, 32).
Subs: Fulton, Kabore, Guendouz, Dhanda, Pollock, Ba-sy
