Failed emission test

[beavis]

hi ppl , im asking you for some help , because i went to the anual inspection , inspection that we are obrigated to do , here in Portugal ...
I´ve swappped an D16Z6 , into my civic K , and all went right till the emission test , that failed with a high value ,passing by far the limit by law ...

my KAT and oxygen sensor is ok , already saw the electric instalation for defects or bad conections on oxygen sensor when i did the swap , and with this i have a theory that i need your knowledge to confirm...

the Z6 OEM honda exhaust manifold , have the spot of the oxygen sensor into that point were the primaries join , into a common chamber , were the sensor can read all the 4 cylinders , the aftermarket exhaust manifold that i have instaled the sensor goes into ONE of the primaries only , so i can deduce that the sensor is reading only 1/4 of the mixture , and the ECU goes to compensate that with more fuel and incrise the emission ...causing my car to fail the emission test , can it be?

[beavis]

any one?

[02EXSILVER]

It's a bit odd. You may need to make friends with someone at an inspection station.


You may be outputting more volume than the stock system, throwing off the readings.

How long has it been since you swap, how many K/M? Mabey you need to finish "burning" everything in first. You may have knocked some ash/carbon loose.

What ECU, or management system are you running? Are you able to check the mapps, and readings? Re-check your sensors too, including the EGR valve.

[daveb91]

What did you fail you just cant say you failed was it high Nox what man cant help if you tell us your full set up and your results..........

[beavis]

im running stock map with P28 , my engine is stock for the moment , and i dont have any EGR valve ...but tested yesterday ,my teory was correct , the problem was the sensor position , when i put the sensor into the final part of my exhaust manifold were the pipes como to only one , the emissions drop down alot to legal values....

[02EXSILVER]

Atleast you figured it out.

Good job, but next time, try to include as much info as you can. It'll allow more people to get a better picture of whats going on.