The West Indies off-spinner snared 3-33 for the Indian Premier League outfit as they secured progression in the Champions League Twenty20 with a 36-run win over Dolphins.
But celebrations were soured when the 26-year-old was cited by on-field umpires Anil Chaudhary and Chettithody Shamshuddin, and third umpire Kumar Dharmasena for a suspect action.
The report was made to the BCCI, who have placed Narine on the "warning list", but he will remain available for selection with the Knight Riders set for a semi-final clash on Thursday.
"Under the CLT20 Suspected Illegal Bowling Action policy, if a player receives a report while on the warning list, the player shall be suspended from bowling for the remainder of the tournament and from bowling in any matches organised by the BCCI until such date as he is cleared," a statement on the tournament's official site read.
With 11 wickets at 7.45, Narine has been the best-performed bowler of the tournament.
Narine was the fourth player to be reported for a suspect action in the T20 tournament, after Lahore Lions pair Mohammad Hafeez and Adnan Rasool, and Dolphins' Prenelan Subrayen.
The reports of suspect actions in the CLT20 do not affect a bowler's availability at international level.