PO 400 EGR valve

consuelo · 03-23-2009, 10:24 AM

Hi i have a 1999 suzuki esteem automatic with 140000 miles and a few weeks ago the check engine light came on,PO 400 code Egr valve, the first thing that i did was to remove the valve and clean the valve an the passages and then i put it back it worked around 50 miles and then the light came on again with the same code so i went ahead and bought a brand new valve from autozone (over 300 dlls ) and this time with the engine running i checked the flow on both passages they were good, so the light went away for another 50 miles and came back on so i took the valve back and got another one (new) and 50 miles later light came on again, and this time i guess that i put more attention to what the engine was doing and i heard the engine knocks, so the engine knocks (it didnt do it before) so im suspecting that its not the egr valve but something else.
Please HElp

jim_naisium · 03-23-2009, 08:59 PM

Unbolt both ends of steel tube and verify that you can blow air throw it.

If that is fine remove the EGR valve from the side of the intake manifold and verify that you can stick a screw driver all the way into the hole on the side of the intake manifold, if you cannot push it more than a couple of inches into the tube then it is plugged up, if it is plugged up spray some throttle body cleaner into the hole and then keep pushing on the screw driver until you break through all the crud.

Once you have made it through the crud spray more throttle body cleaner in the hole and then scrub it out with a very small test-tube brush, that is what I had to do to get my EGR valve from making the check engine light come on.

1999 Suzuki Esteem 1.6 liter.

consuelo · 03-23-2009, 10:15 PM

JI AND thanks but i didnt understand if i need to use the screw driver on the intake itself or on the tube ?

Isuzuzuki man · 03-24-2009, 01:29 PM

Use it on the intake.

consuelo · 03-24-2009, 08:05 PM

you were right the intake port of the egr valve was complketely cloged up i used the screw driver and then the brush with carburator cleaner and it cleaned the port really good, now we are driving it again to see if the check engine light stays off
Thanks for your help

jim_naisium · 03-25-2009, 01:05 AM

Glad I could help, I have put somewhere around 300 miles on mine since I unplugged that tube the Check Engine light has not come on since then.

jim_naisium · 03-25-2009, 03:18 PM

Quote:

Originally Posted by Ehnihl

Better take it to a shop for inspection...

Ummm, why exactly should it be taken to a shop for inspection after an obvious problem was fixed that was confirmed by someone else as fixing their problem as well?

RebelPC` · 03-28-2009, 10:51 AM

I hate to sound like the proverbial broken record here........IAC valve, IAC valve, IAC valve........call me silly but 85% of the time this is the problem with the 1.6l in the 99.....of course if you like i have a tested throttle body assembly for sale for the 1.6 with all sensors included....Dealer cost over $800.....let ya have it for $200 or will gladly explain the process for cleaning the IAC motor.......Thanks!

jim_naisium · 03-29-2009, 09:20 PM

Quote:

Originally Posted by RebelPC`

I hate to sound like the proverbial broken record here........IAC valve, IAC valve, IAC valve........call me silly but 85% of the time this is the problem with the 1.6l in the 99.....of course if you like i have a tested throttle body assembly for sale for the 1.6 with all sensors included....Dealer cost over $800.....let ya have it for $200 or will gladly explain the process for cleaning the IAC motor.......Thanks!

The IAC motor problem and the problem with the EGR valve's air tube are two completely different problems, one effects the quality of the engine's idle speed the other effects emissions control requirements, plus we have already discovered the cause of the problem and corrected it.

RebelPC` · 03-29-2009, 10:59 PM

Quote:

Originally Posted by jim_naisium

The IAC motor problem and the problem with the EGR valve's air tube are two completely different problems, one effects the quality of the engine's idle speed the other effects emissions control requirements, plus we have already discovered the cause of the problem and corrected it.

I am well aware of what part controls what.......but for some reason that after your advice thay felt the need to seek the word of a shop as well......the IAC has caused many different problems for many different people.....sometimes a code sometimes no code......it doesnt not hurt to check it out my friend.........