p0400 nissan frontier 2002

Question

I own a Nissan Frontier XE 2002 2.4 in 4 cilinders, a few moths ago the "service engine soon" light went on, and it reported a p0400 code (related with EGR solenoide), my mechanic told me that it could be a damage pin in the microcontroler computer, I don't know how he got that conclusion, all I know is that he is try to use another computer and make some tests and see if the new computer send the signal to open the EGR, so my real question is What are the condition needed to set the EGR from close to open? because I dont think the computer is damaged

Answer 1

EGR flow malfunction could be caused by a clogged EGR valve or EGR tube. Before replacing any parts try cleaning the EGR valve, tube and passages.