A former city fire marshal yesterday received a slap on the wrist after he was busted for drunken driving and crashing into a police car, injuring two officers.

Louis Garcia had allegedly run a stop sign and smashed into the unmarked NYPD patrol on Dec. 22.

Garcia was initially arrested for misdemeanor driving under the influence of alcohol — punishable by a max one year behind bars.

But under a deal cut with prosecutors, Garcia pleaded guilty only to the traffic violation of driving while impaired and has only to complete a drunken-driving program and pay a $500 fine.

He’ll also have a device on his car’s ignition for six months that measures his blood-alcohol level. If alcohol is detected, the car won’t start.