Did the Key On Engine Off test on my 93 4.9 F150. Got codes 334, 522, and 542. Not sure about the 522 but 334 - EGR closed valve voltage high.
542 - Fuel pump secondary circuit fault.
Now... where do I go from here??? Can someone point me in the right direction? What do I test?

 

Remove the egr valve and clean it. check the relays in your twin tank circuit

 

522 means "vehicle not in park or neutral during KOEO test.