Veteran frontman Phillips came off the bench to secure an FA Cup fourth-round replay for the Seasiders with his injury-time penalty against Sheffield Wednesday on Saturday and his services were required once again after a first career goal from 18-year-old midfielder Conor Thomas put the visitors in front.
Fellow substitute Roman Bednar - who enjoyed such a fruitful alliance with Phillips during their time together at West Brom - marked his Blackpool debut with the cross that left the 38-year-old with a simple 87th-minute finish.
Coventry pressed forward once more and Gary McSheffrey's stinging half-volley might have given them the points, but when Matt Phillips cut the ball across a crowded penalty area in the fourth minute of stoppage time, Taylor-Fletcher was on hand to send the home faithful into raptures.
The win moves Blackpool into the play-off places, ahead of Reading on goal difference, while Coventry remain bottom - seven points from safety and still without an away win all season.
Lomana LuaLua shook off a hamstring injury to start in attack for Blackpool, who made seven changes following their cup endeavours at the weekend
City boss Andy Thorn stuck with the same XI that beat Middlesbrough 3-1 at the Ricoh Arena last time out, meaning on-loan Manchester City forward Alex Nimely retained his place up front alongside Clive Platt following his goalscoring debut.
In a scrappy opening, two sliced clearances from Blackpool goalkeeper Matt Gilks almost presented the visitors with opportunities.
Gilks' opposite number Joe Murphy was down sharply to his left to make the first save of the night, denying Matt Phillips after the winger was released down the inside-left channel by LuaLua.
From his next attempt, cutting in from the right this time, Matt Phillips had Murphy beaten, but full-back Cyrus Christie hoofed off the line.
Christie ventured forward and made space with a clever step-over to curl a shot into Gilks' arms after 41 minutes and moments later he teed up Nimely to exert the Tangerine keeper slightly further.
After Matt Phillips opened the second half by causing more headaches in the Coventry area, McSheffrey had the Sky Blues' best attempt of the match - twisting Alex Baptiste and Craig Cathcart inside-out before thundering a shot that Gilks palmed around his near post.
Thorn's decision to switch to a flat 4-4-2 served to stifle the space that Blackpool had been starting to find as first half wore on, and the visitors had their reward in the 59th minute.
Platt flicked on from Christie's long throw and, as the Blackpool defence hesitated, Thomas prodded home.
Holloway sent on Kevin Phillips and John Fleck in an attempt to rouse his flagging attack, but a loose pass from the latter sent Christie on another rampaging run from deep and as his eventual cross spun towards goal, Blackpool full-back Stephen Crainey was forced to hack clear with Platt in close attendance.
At the other end, on-loan Rangers' midfielder Fleck saw a driven volley deflected wide and in the 77th minute the ball fell to Matt Phillips inside the area, but he elected to square first time and Coventry cleared with ease.
Their resistance was finally broken three minutes from time as Czech striker Bednar broke free down the right and found his old partner in crime, Kevin Phillips, who applied the finish.
As Blackpool sought a quick restart, Murphy, Taylor-Fletcher and Seasiders defender Ian Evatt were booked in an unseemly goalmouth melee.
Coventry sprung onto the offensive and a superb McSheffrey strike had Gilks at full stretch, only for Taylor-Fletcher to break their hearts at the death.