In other words, do they have to do the obd test, or can they do the test where they test your exhaust directly?
The OBD test is based on the year of the vehicle.
1996 and newer are tested from the OBDII connection and not by the emissions coming from the pipe.
OBDII vehicles have sensors that adjust everything to the right amounts to run near stoichiometric amounts. They also factor in engine temperature, ambient air temperature and atmospheric pressure to give the right amount of fuel for the air mass entering the engine.
Before 1996 vehicles had sensors to adjust fuel amounts to give the right amounts to run best but not to cause the cleannest emissions possible.
Even pre ‘96 vehicles must not have a "check engine" light on to pass. But if you have a pre ‘96 vehicle and it is running clean enough to pass you could take the light bulb out and they wouldn’t know the difference.
If you have any other questions about it email me the vehicle info to kormanmike@yahoo.com.
June 14th, 2010 at 5:28 pm
The OBD test is based on the year of the vehicle.
1996 and newer are tested from the OBDII connection and not by the emissions coming from the pipe.
OBDII vehicles have sensors that adjust everything to the right amounts to run near stoichiometric amounts. They also factor in engine temperature, ambient air temperature and atmospheric pressure to give the right amount of fuel for the air mass entering the engine.
Before 1996 vehicles had sensors to adjust fuel amounts to give the right amounts to run best but not to cause the cleannest emissions possible.
Even pre ‘96 vehicles must not have a "check engine" light on to pass. But if you have a pre ‘96 vehicle and it is running clean enough to pass you could take the light bulb out and they wouldn’t know the difference.
If you have any other questions about it email me the vehicle info to kormanmike@yahoo.com.
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