so i had my EGR valve replaced in december and now... well yesterday i got a check engine light. i checked it with my code reader and i got the P0401 code for the exhaust gas recirculation flow insufficient(red light). would it be the EGR valve? or maybe some wiring or the DPFE sensor that needs to be checked/replaced? idk much about cars but i would like a DIY to save some money ...... P.S. got the EGR valve from a mechanic shop.

Also i have a 1999 acura TL :3

 

There's a lot of info here including a diy about cleaning the egr passages. It's a very common problem on our cars. Maybe #2 after transmissions.

 

^ yeah and especially on a 99

 

that's your real problem, ck the diy, buy 3-4 cans carb cleaner and a wire coat hanger
Have fun, its 2 hours at a casual pace with breaks and looking online again~

the egr passage goes inside the intake manifold from underneath that replaced valve thru the opposite end of engine

needed every 75kmiles, acura did a recall 1 time on 99s to install a smooth bore in the port but it still needs to be cleaned thru the length of passage so you get proper flow rate