In front of 1,341 spectators, the home side were good value for the draw, and looked more likely to engineer a third goal in the second half before holding out against a late City flurry.
With an unchanged team for the first team this season, the champions were uncharacteristically sloppy early on, with misplaced passes and skewed clearances.
As City manager John Caulfield had expected, Limerick sat tight and looked to attack on the break and in the ninth minute they created a chance, with three former City players involved.
A cross from the left by Billy Dennehy — playing in the unusual position of left-back — was headed down by Danny Morrissey into the path of captain Shane Duggan, but his volley was over the bar.
With Dennehy at left-back, Killian Cantwell joined Cian Coleman in the Limerick midfield and they did much to frustrate City in the opening stages, though Kieran Sadlier did have a half-chance on ten minutes, shooting over with a half-volley.
The game’s next chance, in the 17th minute, provided the opening goal, as Dennehy showed his relocation hadn’t blunted his attacking instincts. When Aaron Barry’s header fell to him just outside the centre circle in his own half, he was allowed to carry the ball forward without a challenge and from just outside the City D he sent a low shot beyond the dive of Mark McNulty and into the corner of the net.
City sought an immediate response as Sadlier curled a shot wide while Graham Cummins’ cross for Sadlier at the back post needed a good intervention by right-back Shaun Kelly.
Then, Conor McCarthy’s cross from the right was headed to Gearóid Morrissey 25 yards out and his left-footed shot was destined for the top corner only for an excellent Brendan Clarke save.
The chances continued to come for City, with Barry McNamee shooting over after Tony Whitehead got a half-block on a Sadlier cross, while a McNamee free-kick almost fell for Seán McLoughlin in the box but the ball got caught between his feet.
Just after the half-hour, a Sadlier corner from the threatened to cause danger but Darren Dennehy got a good head on the ball for another corner. As that came over, from McNamee on the right, Dennehy was adjudged to have pushed Graham Cummins and Neil Doyle awarded a penalty.
Having scored against Shamrock Rovers on Monday night, and also against Sligo Rovers, Sadlier made it three from three, sending his shot low to the right as Clarke dived the other way.
With parity restored, City sought a lead goal before half. Karl Sheppard went close with a header from another McCarthy cross and in injury time the winger fired over when Sadlier’s free-kick broke in the area.
However, they couldn’t rediscover that momentum on the resumption and Limerick, with Cian Coleman — another former City player — excellent in midfield, began to have the better of the exchanges.
While they couldn’t force a goal chance until just before the hour-mark, two then came in quick succession.
First, Billy Dennehy’s free kick fell for his brother Darren, though he wasn’t able to get his shot on target; then right-back Shaun Kelly, another who played well, did test Mark McNulty with a shot from range but the goalkeeper was able to palm over.
City did make an opening on 66 as Morrissey played in Griffin on the left and he found Sheppard but he couldn’t make Clarke sufficiently work for the save.
Beyond that, chances of a winner were rare. Limerick sub Karl O’Sullivan did have a late shot but it was straight at McNulty and at the other end in injury time, Sadlier had a low free-kick saved, with Cummins unable to reach the rebound.
Clarke; Kelly, Whitehead, D Dennehy, B Dennehy; Cantwell, Coleman; Morrissey (K O’Sullivan 67), Duggan, Kearns (Fitzgerald half-time); Ellis.
McNulty; McCarthy, Barry, McLoughlin, Griffin; McCormack (Howard 80), Morrissey; Sheppard, McNamee (Keohane 70), Sadlier; Cummins.
N Doyle (Dublin).