Man-of-the-moment Michael Mifsud was the Sky Blues' hero once again as he struck late on to deny Charlton all three points at the Ricoh Arena.
The visitors took a first-half lead when Lloyd Sam found the net with a low drive on 15 minutes.
Mifsud was City's main attacking outlet throughout the match and hit the post and saw a shot saved by Nicky Weaver before firing into the bottom corner with just five minutes remaining for his third goal in four days.
Right-back David McNamee's return to the starting line-up in place of the injured Isaac Osbourne was the only change to the home side as boss Iain Dowie kept faith in the side which sent Manchester United crashing out of the Carling Cup in midweek.
After a quiet opening ten minutes, the game sprung into life on the quarter-hour mark when tricky winger Sam latched onto a Danny Mills throughball and fired under Andy Marshall from eight-yards.
Charlton had a good case for a penalty waved away by referee Neil Swarbrick five minutes later when Luke Varney appeared to fall under the challenge of Elliott Ward in the area.
Varney then tested Marshall while a 20-yard Michael Doyle effort was comfortably gathered by Weaver at the other end.
A hesitation in the Charlton defence allowed Mifsud in for the home side's best chance of the half, but pint-sized star steered his shot against the post with Weaver beaten.
A poor punch from Weaver from a Robbie Simpson header then presented Jay Tabb with a good opportunity in the area. However, the City midfielder miscued his first effort before seeing his second blocked by Jose Semedo.
But the Sky Blues continued to press in search of an equaliser after the break and Mifsud forced Weaver to save with his legs from a tight angle after snatching the ball from Madjid Bougherra.
Weaver then got down well to deny Simpson's shot on the turn before Leon Best couldn't find Doyle in area after Tabb's cross had caused havoc in the Charlton box.
But a mistake from the Charlton goalkeeper almost presented City with a chance to score in the 76th minute.
Weaver spilled Simpson's teasing low cross from the right and Tabb nicked the ball from his grasp but couldn't pick out Mifsud or substitute Dele Adebola in the area.
However, Mifsud's determination was finally rewarded with a deserved goal five minutes from time.
The Maltese international latched onto Adebola's knockdown and raced away from his marker before planting a low shot into the bottom corner.
But their was still time for Charlton to go within a whisker of grabbing a winner when striker Chris Iwelumo headed Andy Reid's left-wing cross wide when it was easier to score.
Coventry City: Marshall, McNamee, Turner, Ward, Borrowdale, S Hughes, Doyle (c), Tabb, Simpson, Mifsud, Best (Adebola, 64). Subs (Not Used): Konstantopoulos (GK), De Zeeuw, Kyle, Thornton.
Goals: Mifsud (85)
Booked: Simpson, S Hughes
Charlton: Weaver, Mills, Bougherra, Fortune, Powell, Sam (Holland, 81), Semedo, Zheng, Reid (c), Varney (McLeod, 66) Iwelumo. Subs (Not Used): Randolph (GK), Sodje, Todorov.
Goals: Sam (15)
Booked: Semedo, Mills
Attendance: 19,021 (2,023 Charlton fans)
