has anyone ran into this problem????

im running a jackson charger on mine and just out of the blue yesterday sitting at idle it set this code.

the guy i had bought the car off of had it tuned apparently, but the air/fuel gauge does not leave the rich position... i am wondering where to go from here.

there is a fuel pressure regulator on it... i am unsure how to go about dialing it in or adjusting it, if you even can or not.

has anyone ran into this problem?

any input would be great