OK so today I was sitting at a red light I started to go and it bogged down on me badly I double tapped the skinny pedal and it got up and went but then it started displaying a service 4wd switch message. Any clue what that means? It's a 95 zj( grand cherokee) with the 318 v8 auto trans and NP249 transfer case. It's been stalling in reverse and occasionally at low speeds taking off, what you think clean IAC sensor? What about the service 4wd switch message