Ive got two codes coming up in my truck p0401 and p006b

Question

what do these mean and how can i fix them

Answer 1

P0401 Exhaust gas recirculation (EGR) flow insufficient detected

P006B MAP / Exhaust correlation

For P0401 this is caused by a exhaust restriction or a intake restriction or a restricted EGR cooler.For P006B this is a MAP to exhaust correlation what can set these 2 codes together is a restriced exhaust.