556 code...

[BruhBrahBrad]

Lately I have been getting really shitty gas mileage, even for a untuned cammed 5.0. Im gettting this code, in the KOEO 556 (O,M) Fuel pump relay primary circuit fault - Power / Fuel Pump Circuits. Does this mean my fuel pump is going? I have gotten this code before.

 

[Addermk2]

its a CCRM related code... there are no electrical diagnostic systems that query the pump itself.

 

[Fantom_X7]

http://www.mustang-tech.org/wiki/94-95_Mustangs_Electrical_CCRM This might help. Never had that code before, however I did get poor gas millage as well but that was mostly because of me.