Mike Petizian opened the scoring and former Storm player Liam Hawel had two assists in the win.
Keegan Stevenson had the lone goal for Guelph and Owen Bennett made 30 saves in front of the home crowd at the Sleeman Centre.
The scoring may have not come often, but it did come early as Petizian netted his seventh goal of the season on a shot from the left faceoff dot just over a minute into the game.
Stevenson’s equalizer, which was almost identical to Petizian’s goal, came on the power play at 15:33 of the second period for his 15th of the season.
Pinelli then scored the winner on a 3-on-1 breakout early in the third period.
The Rangers 8-1-1 in their last 10 games and are on a six-game point streak, while the loss knocked the Storm out of first place in the western conference.
Kitchener is back in action at home on Friday against the Niagara IceDogs to open a three-in-three weekend, while Guelph is on the road in Ottawa to take on the 67’s in a game that can be heard on 1460 CJOY.
Larry Mellott will have the call at 7 p.m.