Emissions
Thread Starter
Instructor
Joined: May 2014
Posts: 126
Likes: 1
From: Fairfax Virginia
Emissions
Failed emissions test #1:
High HC (barely out of spec)
Figured since the car was driven about 1000 miles per year and when i got it a few days ago there were cobwebs around the filler cap, I suspected simply that it just needed to be driven with some fresh fuel. Did that. And changed the 02 sensor. Checked timing 6 deg BTDC in Drive.
Failed emissions test #2:
HC was fine, now it was way out of spec on NOx. Crazy.
My thought is to replace the EGR despite it seeming to funciton properly when I tested it. Also changing spark plugs, cap, rotor, AIR pump check valves, air filter, and fuel filter to be changed before next test. My thought is that it is suffering from lean misfire raising cylinder temps causing the high NOx. Could be a clogged fuel filter. Fuel injectors are relativley new and all had 17ohms resistance.
So, anybody have a L98 with high NOx that eventually passed and what did you do?
High HC (barely out of spec)
Figured since the car was driven about 1000 miles per year and when i got it a few days ago there were cobwebs around the filler cap, I suspected simply that it just needed to be driven with some fresh fuel. Did that. And changed the 02 sensor. Checked timing 6 deg BTDC in Drive.
Failed emissions test #2:
HC was fine, now it was way out of spec on NOx. Crazy.
My thought is to replace the EGR despite it seeming to funciton properly when I tested it. Also changing spark plugs, cap, rotor, AIR pump check valves, air filter, and fuel filter to be changed before next test. My thought is that it is suffering from lean misfire raising cylinder temps causing the high NOx. Could be a clogged fuel filter. Fuel injectors are relativley new and all had 17ohms resistance.
So, anybody have a L98 with high NOx that eventually passed and what did you do?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
If the EGR valve was bad, you would know it.
Get a bottle of "Smog chek" from your local parts pimp. That should take care of it.
If not, you are more then likely in need of a new catalytic converter.
Get a bottle of "Smog chek" from your local parts pimp. That should take care of it.
If not, you are more then likely in need of a new catalytic converter.
Thread Starter
Instructor
Joined: May 2014
Posts: 126
Likes: 1
From: Fairfax Virginia
Doing that too. IF it doesn't sqeak past this time, I am going to change out the cats.
Thread Starter
Instructor
Joined: May 2014
Posts: 126
Likes: 1
From: Fairfax Virginia
Passed with huge margin to spare. Spent a grand total of $16. Changed out the AIR check valves on both exhaust banks.
Both were so corroded that they had perhaps 10% air flow. Boom. Done.
Both were so corroded that they had perhaps 10% air flow. Boom. Done.
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I didnt know the do "The Sniffer" in Virginia. The virus is spreading from California into all other states.
This is no good, we need a gearhead POTUS.
This is no good, we need a gearhead POTUS.