Mechanics

P0411 CODE CONTINUES TO COME ON AFTER REPAIRS TO ALL PARTS AFFECTED BY THAT CODE

2000 Volkswagen Jetta • 85,000 miles

Hi, I own a 2000 VW Jetta GLS 1.8T automatic transmission. The car has about 85000 miles on it. Last year, the check engine light came on. I brought it to my mechanic, he checked it with an OBD scanner and code p0411 popped up. He changed the air pump and the code went away. Less than a week later, the light came back on, same code so he changed the o2 sensors. Same thing happened. He also changed the combi valve, checked the hoses for leaks (which there were none), and also checked the vacuum hoses. One was collapsed and he replaced it. His last resort was to update the computer software, which he finally did. The light has been on for over a year now and my regular mechanic cannot figure out what is wrong with my car. I bought a new gas cap for the fuel tank thinking it was that since the very first time it came on was after I fueled up. Any suggestions?
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Jbklyn88
April 12, 2012.




So do you still have the code P0411?Because you mentioned the gas cap.


Saturntech9
Apr 12, 2012.
Yes, still have p0411 code.


Tiny
Jbklyn88
Apr 12, 2012.
When you start up the car when its cold can you hear the air injection pump come on?Also another thing I have seen if the intake and exhaust hoses to the pump get crossed it will cause a air injection code. Also has anyone made sure the ports in the head for the air injection isnt clogged up allowing little to no air into the exhaust?


Saturntech9
Apr 12, 2012.
The air pump does come on and my mechanic has checked for clogs in all of the hoses.


Tiny
Jbklyn88
Apr 13, 2012.
But did they check and make sure the ports going into the head then into the exhaust ports are clear?


Saturntech9
Apr 13, 2012.
Yes, they did.


Tiny
Jbklyn88
Apr 13, 2012.
So did the guy working on your car go thru the trouble tree for code P0411?If so what did he find?Because so far it kooks like he has just been replacing parts in the order he thinks is most likely the cause.


Saturntech9
Apr 13, 2012.
It's a simple system with not too many parts. See attached image.

The only thing missing in the attached image, is the vacuum "solenoid"
that controls the vacuum to hose #16.

Proper function of the solenoid needs to be checked to make sure
vacuum reaches part #10


Tiny
Exovcds
Apr 14, 2012.
Thanks I'll let him know, and I will let you all know if that works! I really appreciate the help and the prompt responses!


Tiny
Jbklyn88
Apr 15, 2012.
Keep us posted on what you find.
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Saturntech9
Apr 16, 2012.

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