still having EGR problems

i have a 2001 2.7l tacoma and As I stated in other posts, I've been havin problems with my EGR valve being stuck open, PO402 CEL code, I took off the valve cleaned it to where I could apply vacuum and the valve inside would move up and down. After fighting with air leaks, it's back on the truck but after 1/2 a tank th CEL came on again. since i know the valve can move, what could be causing the problem? not enough vacuum? the valve is still getting stuck because it is still too dirty?
I don't know what else to try and I'm tired of taking it off and replacing gaskets and what not. any ideas would be helpful. thanks guys

 

could I spray some wd-40 in there to lube it up and help it open and close easier?

 

I'm having the same problem. I have a 2.7 L 2001 Tacoma PreRunner and I got the Error code 'P0401 - ECH has detected too little flow in EGR system.' I've taken the EGR off and cleaned it, cleaned out all the hoses, replaced the gaskets and everything else I can think of, other than replacing the EGR itself. I don't know what the problem is. I'm hoping that the EGR is fixed and I just need to reset my engine light.

 

ever single vehicle that I have owned that had EGR issues was due to the lines being plugged.
Even if you "think" you have cleaned it all out belive me there is more. The worse one was a 2000 Civic HX the entire EGR track inside of the intake was plugged. A 91 Sidekick was plugged from one end all the way to the other.
You have to remove all the lines and insure they are clear from one end to the other.
Chunks are coming off and getting caught in the valve causing it to stay open.
I HATE EGR SYSTEMS!!!!

 

well i took my EGR off multiple time and cleaned with sea foam deep creep and WD-40 and took off all the line and made sure they were not clogged but the CEL would still come back on so finally i gave up for a while and then about 2 weeks after i had cleaned it the CEL randomly went off on its own and hasnt come back on and my Ultraguage hasnt detected any problems. so maybe it just takes a while to the truck to realise it is working correctly again, who knows

*make sure you replace the gaskets and make sure there is no leaks...

 

seafoam and wd40 WILL NOT clean it out. Believe me it is caked on there and is otherwise as hard as a rock and chemicals will just not remove it. I had to use rods and brushes and even knives to get my EGR's clean.

 

you are right, everything was caked in there and pretty solid, but i used the seafoam and wd-40 and scrubbed with everything from tooth brushes to my wire brushes i use to clean my gun barrels...no more CEL means it worked for me

 

congrats on the fix

 

thanks, it was a pain in the ass to take the EGR off so many times but it was a learnign experience and it worked, eventually haha

 

It was for me as well! Good job!

 

I used carburetor cleaner to clean the EGR (let it soak for about 2 hrs) valve and pipe cleaners to clean out all the tubes, as well as replacing the gaskets and my problems seem to be fixed. If your light doesn't go off, you may need to reset it by unhooking the negative battery terminal for about 5 mins.

 

i had reset that light every time i pulled the EGR off to try an fix it, it always came back on, so once i knew it wasnt a valve issue or a vucuum issue, i just left it alone and then it magically went away on its own and never came back...

 

im not sure about these trucks, but when we typically have an egr issue in nissans/infinitis here at work it ends up being a blockage or partial blockage somewhere in the egr system. it takes a wire brush and lots of brake clean to get all that garbage out.

 

thanks for the rep BTW

 

Well, my check engine light came on today, so everything I did didn't work. I'm going to take off the EGR again and scrub with a wire brush and clean all the tubes out again and hopefully I'll have some results.

 

yep, it can get tricky. The Civic HX I had cost me $412 for a new EGR valve. So taking your time cleaning it first is well worth the effort.
Like I said each of my cars that needed it took a week of taking it back apart and cleaning it over and over until I got it all out. I even let the parts seat for 3 days in a bucket of gasoline and then carb cleaner and it didn't budge. Had to just bust it all out using coat hangers and anything around that was sharp and narrow that would get in there!

 

what code is your truck throwing? is the valve stuck open/close? mine was EGR excessive flow (stuck open) either way, apply vacuum to the top of the EGR and see if you can open and close the valve, then lube and clean more until it gets easier to open/close. then check your modulator - make sure air can flow through and check the little filter in there. my CEL kept coming back on between 20-150 miles after cleaning (which i tried 3 or 4 times) so i left it alone for a week or so and then it went off, so just give it time i guess.
there are some good threads on here, give me sometime and i can find them.

 

here ya go

 

mine was the opposite. No flow.

 

im no expert but there is probably a blockage somewhere. if u know the valve isnt stuck shut (it opens when u apply vacuum) take off all vacuum lines and make sure there is nothing in them, then check the tube from the exhaust manifold to the EGR for blockage, next check that the modulator is working. then lastly i would test the VSV valve for the EGR.