got a check engine light on today so i got my OBD II scanner and i got the code P0401 Exhaust Gas Recirculation Flow Insufficient Detected. I suspect that it has something to do the the EGR. anyone had this code or DIY things i can do to try to fix or find out the cause of the problem. thanks

 

What year and model Civic? Have you verified that your Civic has an EGR system? For 6th generation Civics, I think only the D16Y5 engine has this system.

Clear the code and run the car to verify that the fault repeats. If so, here's how to troubleshoot:

 

i just got the code cleared. i have the D16Y5 engine. thanks for that diagnostic, i will give it a try

 

Any updates on this? Mine 2000 HX is throwing the same P0401 code

 

Try this link. I had the same problem on my HX.
http://www.tegger.com/hondafaq/egr-fix/index.html

 

does your car come with an egr? year make and model would be helpful for diagnosing