buddy of mines did a smog test today, everything pass besides emissions test.

readings
15mph NO (PPM) Max: 807 Ave: 237 Meas: 899
25mph NO (PPM) Max: 746 Ave: 199 Meas: 919

what is this and how do we go about fixing it?

 

the cat or o2 sensor is bad...change either one or both and you will pass with flying colors...been there done that...!!!

 

Ouch!! Your cat converter is dirty and the O2 sensor may not be reading properly. Your car's emission reading passed the max allowable CO2 PPM.

Solution: do what BiG ChOr!Zo said :D But let it be a reminder to keep up with scheduled oil changes. That's the common causes that leads to bad emission.

 

i thought HC is cat or o2 as well? my HC is always very close to failing

 

You don't need to change both sensors, just the primary. The secondary just tells the computer if the cat is working, your CEL would be on if either the cat or the sensor was bad. When was your buddies last tune up? Do a basic tune up before going in for the second test. Replace the plugs, wires, cap and rotor, oil change, PVC valve... And right before going in run the car close to 4000 RPM for 10 minutes or so to get the cat converter hot, the cat works better in high temperature.

 

no codes. the car had pass smog last year with my cat. he sold the car in beginning 09 and just bought it back last week. dont know the recent tune up but ill let him know to do all that and everything else you said ahcapone.

if o2 is bad, isnt the code 1 suppose to show up or the code 43 (fuel supply system, o2 is a cause of that code too)

 

Just passed emmission today. check your cat and for exhaust leaks.

 

NOx pollution is caused from too high of combustion temps. Running lean or having a failed EGR both increase temps, increasing NOx emissions.

Check the EGR valve, if the car has one, and clean/replace as needed. Might have a lean injector, and cleaning them is never a bad thing (if done right).

Also, in a modern cat the first stage breaks down NOx to use the O2 in the 2nd stage to burn the HC (unburned fuel). How's the HC numbers? If they're high, it could be the first stage ofthe cat failing.

 

This all sounds very confusing. The car had the spark plugs and wires replaced not too long ago, cap and rotor are fine too. im sure My_EFsedan could help me with cleaning the injectors and doing the pvc valve, the car passed smog about 6 months ago but the old owner said it barely passed. This is alot of work i should just do illegal smog

 

i already said what needed to be replaced above...if you want to keep blowing money on other parts that don't need changing then so be it...if i was you and want to save money just apply to the CAP program with the state bar and they will pay up to $500 to help you pass the smog check if you have failed on the original test...just a note that you need to have the stock motor in the vehicle and be the registered owner to qualify...!!!
http://www.bar.ca.gov/80_BARResource...sist_FAQs.html

 

i just need to smog it so i can register it in my name, after thats done the motors coming out

 

just do a complete tune up and take it to get smogged...if it passes you win...if you fail then apply to the CAP program...end of story

 

yeah i have another 30 days to get it smogged and its free, ill just get an oil change, probably drop down the cat to see if anything is wrong in there, if it fails again. ill just pay the price to MAKE it pass

 

tunerN00b is right check the egr....and someone mentioned CAP..cap will assist in paying for the parts to make ur car pass BUT it can only be used if the car is already in ur name and to be eligible you have to spend like minimum $300 in parts and labor in a gold shield location to fully complete the application then CAp will assist u up to 500...

 

FALSE
you are right in having to be the registered owner to qualify for CAP but you absolutely do NOT have to spend $300 at a gold shield station to complete a application...to be elligible you have to fail a regular smog check or a test only to qualify...you only have to pay a co pay of $28.25 to the gold shield station after repairs are made to your vehicle if you participate in the CAP program...!!!

 

i got a new cat drop did pretest didn't passes i had a high idle and timming was at 10 now i got the timming is at 16 and idle is at 750 to 900 now i do have header and a Secert WR intake my muffler is stock does my header or intake matter
p.s. i live in Cali

 

^HIGHJACKER!!!