Diesel Place banner

Codes P0401, P0404?

13K views 9 replies 9 participants last post by  Jeep23  
#1 ·
I have DTC P0401 and P0404. I know they have to do with the EGR. Im pretty sure the 0401 has to do with my perf exhaust and maybe my AFE intake. I was told that the EGR blocker and fingerstick wld fix this one. Or the PPE tuner. But what about the 0404? How do i fix this code? Will it turn off as well, with the mentioned fixes. Is it bad for the truck if i drive around with these codes? Do i need to replace the EGR? Lots of quest huh!
 
#2 ·
Since its an LLY the emissions codes shouldn't bother the truck unless it's a CA truck I believe. I shouldn't derate or anything because I know mine has EGR related codes( I forget what ones) and has no problems or lights on.
 
#3 ·
finger stick will fix it....egr block is just another nice mod to do.
 
#5 ·
Sounds like your exhause may be causing these codes. Put a Finger Stick on it and clear the code. Though not required, many have blocked their EGR.
 
#6 ·
I have a blocker plate with no finger stick and have had by EGR valve unplugged for 25,000 miles now and have the exact same codes as you without a CEL or anything else.

The only thing that could be a potential problem is if you had to have a dealer work on it, cause they may see those codes and start asking questions or start fixing problems that don't really exist.
 
#7 ·
EGR......... It wont cause any performance issues, best bet it to buy and egr blocker. I throw both of those codes with my blocker plate in with stock tuning. Nothing to worry about, other than your CEL is probably annoying.-:t
 
#9 ·
Jeep23, I guarantee that you have engine codes, just no CEL. If you were to scan your truck you'd have 401, 404 and a 16XX code as well but I can't remeber what it is right now. Your emissions package just happens to be one of the ones that "doesn't care enough" about it turn on the CEL.
 
#10 · (Edited)
Yeah, I do have codes. And I was saying that even though I do throw the same codes as he is, it's no effecting anything. But yes, I do have codes. In fact, I think I said that I have codes in my intial post. I don't know!!! I don't feel like going back to read it again!!!