then your state is not an IM240 testing state. You need a load to actually test the car in real world situations, but apparently oregon isnt at that level of emissions testing.

 

of course the car expells gases when its not moving; its just not anywhere near the amount that it is under load. you cant have a real test without load conditions.
Your state may not perform loaded tests such as an IM240 test.



revving the car engine in nuetral is not even a 5 percent engine load situation.

 

well in mass with my AWD thats what they had to do to, just reving it. Then when it failed the guy then did it without doing anything, just the sensor in the pipe, and i still failed by double the state standard . I got rid of the car before i had it fixed but im pretty sure it was a bad cat.

 

what does your state have then? here in washington we don't need that, and when spinning the wheels it's the same load they keep it at the same rpm's wouldn't it bee the same load when the engine is working the same. once the wheels start going the load goes down from force of gravity.

 

there is certainly NOT the same load sitting still revving the engine as there is driving. You may only need 10 HP to stay at a constant cruise, but you will need 100 to get it there.
higher revs are not what creates high levels of NoX; thats caused by high combustion temps, only reached at high load situations.

An IM240 test is the nation standard in polluted areas. If you dont live in one, you probably will someday. check out a couple links for more information.

http://www.aa1car.com/library/im240.htm

http://www.wivip.com/index.html?te_im240.html

http://www.epa.state.il.us/air/vim/faq/testing.html