Smogtips
CHOOSE YOUR CITY OR ZIPCODE:
Within:
SELECT SMOG CHECK TYPE:  

Join the community and post your question. Use our Ask-A-Tech for free now! ASE experts standing by.

Forum > Failed Smog Test > Question

1998 Honda Civic EX Failed Emissions and Functional

Hi there. I'm trying to figure out how my Functional Check and Emission Test Results were a PASS but because of my air intake(after market) and missing PCV hose I was failed for the 1st smog test and was told that the reason was because the air intake needs a EO# and the PCV hose needs to be connected.

I went home swapped out the air intake with the stock intake and connected the stock PCV hose also. Took the 2nd test that took WAY longer than the 1st smog check because the technician was busy trying to explain why a different customers car didn't pass while all along my Honda Civic was connected to the smog machine for a good 10 min with nobody attending it.

But back to my situation. So the 2nd smog test was done and the helper of the smog technician tells me that she had good news and bad news. My car had now passed the visual and functional part of the smog inspection but not the emissions part.

I just want to know what could have caused that when all I did was put in the stock intake and the PCV hose back on my Honda Civic or could it have been a mistake done by the technician? Thanks for your time.


Answer:

Switching the aftermarket air intake unit you previously had installed on your Honda Civic to the original air intake box would have made a minimal difference on the smog check emission results, assuming the aftermarket air cleaner was identical in connections to your Honda's original air intake.

The PCV being connected is where the emission result difference comes into play. Depending on how the PCV was originally NOT connected, ie. missing and allowing unmetered air in to the intake manifold or missing and intake manifold plugged, or simply broken and allowing unmetered air into the intake manifold, the emission results would have changed on the subsequent smog check.

At this point it is necessary to inspect your Honda Civic's smog check results with the PCV connected and functioning. It is possible your Civic has other emission problem(s) which were masked by the improper operation of the PCV valve/system.

In our expert opinion, the smog station more than likely was not responsible for your Honda Civic's smog check failure. It is quite common for a vehicle to fail the smog test after a known smog fault is corrected; requiring further diagnosis down the flow chart.

Should you like to use our Online VIR Diagnosis System we can look further into why your Honda Civic failed the smog test. It will be important to know the smog check results of the CO, HC, and NOx emissions.


posted by SmogTips Support

 

View SmogTips.com in: Desktop / Mobile