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99 honda accord ex EGR valve code p0401


leguligu
05-06-2007, 03:04 AM
Hi, guys. my check engine light came on six months ago. i took my car to autozone. they gave me the code P0401 (EGR Flow Insufficient). I changed the new egr valve and cleaned the egr port and passage that connect to egr valve. but the code is still on.:banghead: My car is 99 honda accord ex 4 cylinder. now mileage is110000. I am a newbie. Is there any egr port inside the intake manifold. If yes, Do I need to take the intake manifold cover to clean those egr ports. How to do that. Guys, I really need your helps. Please. Thanks.

somick
05-07-2007, 11:32 AM
Did you clear the code from the ECU memory after repairs?


Sam

leguligu
05-10-2007, 01:53 AM
I have tried to disconnect the battery and pulled out he backup acc fuse. The light just turned off like one day and then come on again. Can you tell me are there any egr port inside the intakn manifold? I really need your help because i have to inspect my car next month in New York. Thank you!

jeffcoslacker
05-10-2007, 04:07 AM
OBD-II trouble codes have to be cleared with a scan tool...the ECM holds hard codes in memory even with power disconnected.

You've got a passage through the intake yes, but if it's clear near the valve, it should be clean all the way through...near the valve is usually where they develop build-up. I don't like to get too crazy trying to clean the intake side, you don't wanna force a bunch of solid crap through to have it blown into the cylinders.

You can go to AutoZone and have them clear the codes, see if it comes back. They're supposed to clear them when they retrieve them, but sometimes they don't, and it just keeps popping up.

blacknight
05-11-2007, 10:56 AM
Click here to erase your CEL code (http://www.6thgenaccord.com/forums/showthread.php?t=1716)

leguligu
05-11-2007, 02:31 PM
Hi, guys. I went to autozone to clear the code. but the the CEL come on again after one day. Do you know are there a EGR plate port under the intake manifold cover. If yes, how can I clean those egr ports inside the intake manifold. does anyone can post the picture of the clearning egr port. Please help me. thanks a lot.

mpumas
05-11-2007, 04:27 PM
What turns on the EGR cel is a ECU determination that the MAP changed after the EGR actutated. You said you cleaned the EGR ports---did you remove the plate that goes from the EGR valve to the individual intake manifolds for the cylinders? If not, you need to do this to get to get to the ports that enter the intake manifold. I don't know what it looks like on the 99 but on the 97 it is a sheetmetal tube/flat plate that is bolted on with about 3 or 4 bolts. When you remove the plate you should see the holes that enter the manifolds. You will need to drill them out using a drill bit attached to something you can turn by hand. (Honda recommends using carburetor cleaner) Replace all gaskets and seals. If you did that, then the problem may be a clogged line before the EGR valve. Compressed air should be able to determine that. .

Glen_T
05-14-2007, 09:03 PM
Per the manual (and my I-4 98), I do not believe there is any coverplate for the EGR passage like the pre-98 engine had. It would appear that the cylinder head has an internal passage from the exhaust side to the intake side, and the intake manifold has a passageway to each runner.

If the EGR valve was replaced and you're sure the passages are cleaned, the manual has you remove the EGR connector, then apply 12V to the #4 pin (would have connected to the pink wire), then start the engine and let it idle. You then ground the #6 pin (would have connected to the black wire) and the engine should stall or run really rough.

What you are doing is opening the EGR valve completely which should kill the engine. If it does, then the manual says the system is ok, and that the problem is intermittent. So, I'm guessing that the system can tell that the electrical side is working ok by using the position sensor.

I'd guess that you need to clean the ports better, maybe you could call your local Honda service desk and ask what they use. My dealer is pretty good about sharing "tips". Maybe they use a bristle brush or something to break things up, then suck it out with a vacuum cleaner.

Hope this helps...my 98 only has 69K on it, so maybe I'll be in the same boat soon....let me know what you find out....Glen

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