NOx?

Comments

• SiWagon Council Member

  March 2006

  Did you add a Cam Gear ,when u swapped heads?
  :idea: Try retarding the timing & put in a can of that "Pass your Smog"(Not the real name) stuff from the parts place.This should help drop the NOX.
  
  Lots of Luck.
• davens familEE

  March 2006

  Nitrogen Oxides in vehicles are caused by excessive combustion chamber temperatures. Some of the common causes of high NOx emissions are problems with the vehicle's Exhaust Gas Recirculation System (EGR)[Only HFs have an EGR], improper ignition timing, lean air/fuel mixture and malfunctions in systems that control engine temperature, such as the thermostat and cooling fan, and vacuum leaks.
  Typical high NOx culprits (clipped):
  Misfire condition
  Failed oxygen sensor
  Leak in exhaust tubing upstream of converter
  Excessive carbon deposits in combustion chamber
  Improper spark advance
  Overly lean air-fuel mixture
  Corroded or damaged engine sensor electrical connections
  A failed catalytic conv. could contribute to high NOx readings but the cat failure itself is most likely caused by some other problems, like improper air-to-fuel mixture.
  
  Given your previous post about your o2 sensor, I'm putting my money on a lean air-to-fuel mixture. If you're running lean, you're going to be running hot.
  There are plenty of possibile culprits that could choke the fuel system...clogged fuel filter or injectors.
  First cheap steps: verify good fuel pressure, new fuel filter and a couple doses of intank fuel injector cleaner.
  
  A slightly ghetto way to knock down combustion chamber temps is trying spark plugs one heat range cooler.(look it up)
  But I think that there is something wrong in the stock setup that when identified and corrected, will let you pass NOx.
  
  [edit]I just noticed you did a y7 head swap? Any idea what compression ratio you're running now? I'm guessing more than 10:1. Higher compression ratios will increase combustion chamber temps...Stock crappy DPFI trying to feed fuel to a higher compression ratio might be the problem. More fuel than stock or higher octane might be called for.
• marc-111 Wagonist

  March 2006

  just passed NOx today!!!!
  
  what i did was changed the airfilter and cleaned the muffler by sticking a hose with water flowing through it and rev the living s#it out of it! it was so dirty as in black
• akiraboy HondaCivicWagon.com Founder

  March 2006

  hmm never heard bout the garden hose thing before :shock:
• marc-111 Wagonist

  March 2006

  hehehe! tried and tested on our diesel vans before to pass
• davens familEE

  March 2006

  akiraboy wrote:

  hmm never heard bout the garden hose thing before :shock:

  
  
  "Yeah, my car failed emissions...so I washed it and it passed."
  
  ...I don't know if I would be admitting that
• akiraboy HondaCivicWagon.com Founder

  March 2006

  would this work with a pressure washer too or is this not a good idea
• MrKISS Band Wagon

  September 2006

  I got an emissions waiver on NOx in NJ on my 86 2wd Wagon [104K miles.] The waiver is issued if the vehicle is over a certain age and the owner has spent a certain amount trying to rectify emissions probs. I think my prob is the cat converter...everything else was fixed.
  
  But it's only good once; ie, if you sell the car, the new owner cant get another waiver if it fails again. If the vehicle is sold, it still must be inspected for safety items.
  
  Be alert for Honda Dealer personnel and DMV workers not being informed on this.
  
  What is the deal w/ running a garden hose into the car? It's run into the muffler? Details?
• Kahuna familEE

  September 2006

  Jeeze, I'm so glad we don't have inspections here. They sound like an annoying hassle.