Emmision System

I had my car inspected and it didn't pass the emission test. NOx(ppm )
current reading is 2199 (High Speed Emission) Low Speed Emission reading
was 2595 . Can you please help, and advise what may be the cause for such
high reading?

 

Um, what's it supposed to be to be within specs?

 

Well accroding to the Reading Standard High Speed Emission (25 MPh) is NOx
(ppm) 984 min reads 2199
and Low Speed Emission Resupts (15 Mph ) Standard is 1088 mine reads
2595

 

does the car have EGR? that directly effects NOx readings.

 

Sorry , but what is EGR? it's a 91 automatic accord.

 

Exhaust Gas Recirculation. Some of the exhaust is pulled back into the
intake to dilute the air/fuel mixture. This is done for the sole purpose
of reducing NOx emissions. Not all cars use EGR, but on cars that do, a
faulty EGR valve can cause problems with increased emissions.

What trim level (EX, LX, DX etc.) is your car, and what engine does it
have?

 

EGR only works at idling, on 1 cylinder.

He has serious high temperature in the combustion chamber, perhaps excessive
carbon deposit? Or a faulty Cat?

 

High NO is caused by high combustion temperature, such is resulted from
either advanced timing or carbon buildup in the the combustion chamber.
If this is my car, I would run a bottle of combustion cleaner and change the
timing to the minimum. If that still not reduce NO enough, then I would look
at the catalytic converter.

 

Thanks for the information , i will try this