Ok I have a 99 dodge Durango 4x4 with the 5.2 and its burning really rich I e changed the up and down stream o2 sensors and it hasn't changed and here lately I've had problems where when I'm driving the motor just dies no sputter it just dies like you turned the key off and as long as I'm doing at less 40mph it will crank itself back up and it is getting to where its during if I have it idleing for long periods of time what can the issue be

 

I'd start by checking the battery/battery connections and maybe the IAC.

 

I've already checked the battery and that not it and what do you mean the IAC the only code that pops up is output speed circuit

 

The idle air control valve on the throttle body. A speed sensor isn't going to keep the motor from running.