P0401 EGR Code Lingering then Engine Misfire

Joined
Apr 29, 2019
Posts
18
Reaction score
0
Location
Houston, Texas
Hi everyone,

Been having some issues with my 2001 Honda Accord EX 2.3L 4 cylinder. About a month a half ago I ended up getting a code of P0401 Insufficient EGR Flow. From my understanding, these cars tend to build up a lot of carbon through the EGR port between the intake and the EGR Valve.

Anyways, for that month and a half, I ignored it. Finally one week I decided I was going to fix the code on the weekend, but by the middle of the week my car started misfiring.

I then had the following codes:
P0300 Random/Multiple Cylinder Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
P0401 Insufficient EGR Flow

I've read that due to insufficient EGR Flow, it could make the engine misfire. Decided to take my chances on cleaning the EGR port between the intake and EGR Valve and also cleaning the valve itself.

This was performed this past weekend and the car is still misfiring. I cleared the codes, but then I end up getting the following codes:

P0303 Cylinder 3 Misfire Detected
P1399 Valve clearance out of range (Not sure what this means exactly)

Should I take my chances and buy a new EGR Valve? or am I missing something here? Originally I thought I would have to clear the EGR ports in the EGR Chamber BUT i saw that these 2001 honda accords don't have that chamber. I've cleared what I could.

Ideas? Thanks to anyone that replies in advance :)
 

BlkCurrantKord

Super Moderator
Joined
Sep 7, 2005
Posts
9,870
Reaction score
85
Location
Ohio
Depending on how bad the gunk build up is, you may consider a few rounds of seafoam and a cleaning the ports out by hand with some brake cleaner and pipe cleaner.
 

dpham671

Member
Joined
Jan 18, 2020
Posts
22
Reaction score
0
Location
Los Angeles, CA
I'm pretty sure your EGR valve is ok, I had the same problem and thought it was the EGR valve. Here's a link to the video that I followed to fix P0401.
At the 3:39 timestamp on the video where the arrow is pointing, did you clean that port? It's about 3/4" in diameter and it will be caked with carbon. Seafoam is good stuff but useless for this repair. You gotta remove your intake manifold to clean it out. Seafoam or similar solvents will not reach the clogged port. If you're mechanically inclined just follow the video step for step and it fix that Pcode for sure. possibly the other codes as well. Yes I have done this and in my opinion has the best explanation on how to fix it.
 

INK DEMON

Well-Known Member
Joined
Nov 29, 2008
Posts
79
Reaction score
10
Location
SAN DIEGO
Hi everyone,

Been having some issues with my 2001 Honda Accord EX 2.3L 4 cylinder. About a month a half ago I ended up getting a code of P0401 Insufficient EGR Flow. From my understanding, these cars tend to build up a lot of carbon through the EGR port between the intake and the EGR Valve.

Anyways, for that month and a half, I ignored it. Finally one week I decided I was going to fix the code on the weekend, but by the middle of the week my car started misfiring.

I then had the following codes:
P0300 Random/Multiple Cylinder Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
P0401 Insufficient EGR Flow

I've read that due to insufficient EGR Flow, it could make the engine misfire. Decided to take my chances on cleaning the EGR port between the intake and EGR Valve and also cleaning the valve itself.

This was performed this past weekend and the car is still misfiring. I cleared the codes, but then I end up getting the following codes:

P0303 Cylinder 3 Misfire Detected
P1399 Valve clearance out of range (Not sure what this means exactly)

Should I take my chances and buy a new EGR Valve? or am I missing something here? Originally I thought I would have to clear the EGR ports in the EGR Chamber BUT i saw that these 2001 honda accords don't have that chamber. I've cleared what I could.

Ideas? Thanks to anyone that replies in advance :)


To answer your question: Valve clearance out of range means that the valves need to be adjusted.



Although the fact that you got the EGR code first, I would recommend you start there and remove the top part of the intake manifold as another poster already suggested.

However, at this age, I'm sure the valves need to be adjusted too.
 
Back
Top