A Tripy Makonda own goal cancelled out Kamel Chafni's first-half opener but Lyon failed to break the deadlock again on a pitch resembling a Wimbledon tennis court in its second week.
The result left Lyon with 52 points from 27 games, two adrift of PSG who lost 1-0 at 10-man Stade Reims on Saturday.
"We would have liked to take all three points but we were caught cold," striker Bafetimbi Gomis told Lyon's official website.
"But we're going forward and we're getting closer to PSG."
Substitute Sougou had set up the first OM goal a minute earlier, perfectly crossing for Nicolas N'Koulou who was at fault for Troyes's opener.
Bottom side Troyes went gone ahead in the 70th minute after Marcos had dispossessed N'Koulou before firing a powerful cross shot past Steve Mandanda.
Lisandro came close for Lyon in the 37th minute but Alexis Thebaut parried the Argentine's powerful angled shot.
Kalou, used as a lone striker at Lille, dribbled past Benoit Tremoulinas and beat Cedric Carrasso from close range in the 72nd minute after Ronny Rodelin's fierce strike in the 59th had cancelled out Jaroslav Plasil's first-half penalty for Bordeaux.
