hello
i have a 2002 Honda civic EX.i have a code P0401 related to EGR valve.i remove the valve and cleaned ,got new gasket also spray the intake hole, and code was gone.however after driving some miles i get the CLI/code back.i think i may need to replace the EGR(noticed rust on the valve body.look like previous owner lives near sea or a place with lot of moist).my things is that the nut on the right side due to rust do not come out alone,it come out with the bolt/stud.and i want to replace the stud and nut when i replace the valve.i had search several of the Honda web sites and do no find this stud/nut part.if anyone know the part number please let me know
the stud and nut are the one that hold the EGR body to the motor.
thanks for any help.

 

Soak it in penetrating oil, then separate the two. Or just reuse it the way it is. It won't hurt anything.

 

it wasn't me..thanks a lot....thanks ...i got a set of bolt and nuts from local Honda cost $3.00,was a surprise that it cost only that..now to the next step.
look like previous owner did not have any mechanical inclination.i was checking on the air filter and noticed that the plastic air cleaner assembly is broken in the 3 places the screws attach to the cover.look at hoda and it cost $50.now my son told me about cold air intake,same cost....is cold air intake better than the regular factory air cleaner assembly?

 

You're not going to find a CAI for $50. An ebay knockoff SRI (short ram intake) maybe, but not a CAI.


Better? Not really. Both clean filter the air, but the SRI or CAI will just make a lot more noise while doing it. People add them thinking they're going to get some sort of performance increase, but really all they get is a placebo effect. They only think they're increasing performance. Knowing this, some people still install them simply for the appearance and noise factors.

If you're going to buy one, buy a short ram, but make sure it has a good filter on it.


Personally, I'd just replace the OEM unit. I've seen complete (used) ones on craigslist for $50.

 

hello again...i have a p0401 code problem.i had clean the egr valve and intake hole couple times.code go away for 10-20 miles then come back.then i ordered a new egr valve,got it today.replaced the old one.code was gone until i drove for 10 miles and code back again.i had noticed that when i am at stop/or red light and then go the 1st and 2nd gear the idle sudden goes up and then back to normal(do not know if this is related to egr code p0401.do i need to do anything else after i installed the egr valve?.i can't erase code because it was gone after i replaced the part...thanks

 

Might have enough carbon buildup further into the engine to cause the insufficient flow. First, go ahead and reset the ECM/PCM anyways: With the ignition off, pull fuse #6 in the under-hood fusebox. Then let it idle for 5-10 minutes with no load to set the idle. If the code comes back again, remove the EGR and spray carb cleaner in the hole in the engine- as much as you can, fill it up. Let it sit overnight then clean it out with the corner of a clean rag. Engine may race for a sec or two on startup.

EDIT: The only reason I would go with SRI is it's easier to get to stuff, you don't have to take that big azz air resonator box out of the way.

 

thanks for the answer.now what do i need to have off not to let it idle up for 5-10 minutes?like the fan,radio,?

 

Sorry, should have added: Keep it at 3000rpm until it gets to operating temp. Then let it idle for 5-10 minutes with no load. No load means nothing on- no lights, A/C, radio, windows, etc.

 

When I removed my intake to replace my cylinder head, the egr ports in the injector plate were completely blocked with carbon.

I don't see how the system could of been working, and not throwing a code.

 

one question., with car running on parking i unplug the connection from egr valve,the CLI do not come on.is that OK? ...thanks

 

You can't test it that way. You have to run jumper wires from the battery to specific terminals on that connector. That test only tells you that the EGR is bad. This specific code (P0401) is only for a bad EGR. All the other EGR codes deal with shorts or a bad ECM/PCM but, not this one. I think MarkM01 is on the right track ("the egr ports in the injector plate were completely blocked with carbon") as this specific code is for "insufficient flow".

 

thanks you for the help..i sprayed a whole can of carb/intake valve cleaner in the egr intake ports.the code goes away and after 10 miles comes back.
OK" this is what i have done so far
1-egr valve is new,so i know the valve is good.
2-sprayed ports
3-reset ECU...
still code is returning.
by the way when i removed the new egr valve to do the last cleaning of the intake ports,i noticed that on the square hole on the egr valve assembly and on the intake port there was a good amount of black dust.now taking this in consideration i thinks there must be a very large amount of carbon buildup in the intake ports and will require a better cleaning,.i used napa carburetor/intake valve cleaner.
is there an other better cleaner?. is there another way to clean this than spraying the egr intake ports?
thanks a lot

 

Probably have to take the throttlebody and/or heads off to get to those ports.

 

thanks...
i can see that the place where the egr valve seat is a piece that is attached to the motor,look like is attached with bolt,nuts.no sure.this is a 2002 civic EX vtec 1.7L.i am going to get me a repair manual.here in Delaware i do not trust much the dealer repair shop,and many of the mechanic here are more into American card.i had had my bad experience with them.

 

Worth every penny: http://www.helminc.com/helm/product2...C01&itemtype=N

 

hello again.
has anyone removed the part where the EGR valve is set on.this part is a small block next to the motor near the valve cover on the left side.on that small block beside the egr valve also are 2 sensor,one look like a water temperature sensor,also the thermostats housing and other cooling hose are there.i see that the block is not a whole with the motor and is attached with 4 studs/ nuts.also there is what look like a metal gasket between this part and the motor block.this 2002 Honda civic EX has a bad case of carbon in the egr intake port.i had sprayed the port 3 time.2 times used whole spray can.code leave and after few miles returns,i can drive the car but sometime the idling get annoying.if i can remove the part mentioned above maybe i can do a better cleaning...i got a manual but all it teach is how to test the egr valve and to clean port with spary and i have done all that...thanks