OBD II readers

[johnholl]

Can the code erasure function on the OBD II readers help a car pass these crazy emissions systems \ inspections? My state has recently adopted this test on all vehicles post 1996. Money grab, in my opinion. It's the older, exempt cars that are poluting. These emmision parts are very expensive, and should be covered by the manufacturer. In many cases it's a very costly hit or miss replacement proceedure, with respect to the components, and if the mechanic doesen't properly interperate the data correctly, it can cost an arm and a leg. Can you tell I'm pissed?

[DRW1000]

It all depends on where you live and what the rules are. I am not for cheating on an emissions test but I will share what I know for the sake of information. Personally I think you should fix the problem you are having as it will most likely increase your gas mileage as well as help the environment.

An OBD11 vehicle keeps track of emmisions related sensor readings and will flag the CEL to illuminate if a problem exists and a code is set. The code can be retrieved via an OBD11 code reader. When a code reader erases the code it also erases the state of the built-in tests (called monitors). There are up to 11 monitors on an OBD11 vehicle. Although the CEL will be off temporarilly the "monitor-not-run" flags will be set and the test equipment will consider that the vehicle is not ready for testing and may send you away to drive it some more. When the monitors see enough drive cycles they will run their tests and the CEL will probably come back on assuming that you did not correct any prior failure. The monitors all take different times to run their tests. My EVAP system monitor took about 5 days to run its test.

The test facilites also look to see that the CEL will illuminate at start up to ensure that someone did not simply disconnect the bulb.

Even if you were able to fool the test people the test equipment would still read your emissions.

In my province the state of the monitors was considered at one time. In fact they would not test you if you were dripping excessive oil but this changed due to the following:

-Leaks are subjective and different facilites would have different opinions and of course there was no consistency.
-They also decided that it doesn't really matter what the CEL is doing or if the monitors have run as long as the tailpipe is not producing out of allowable range emissions.

This means that I could go to a test facility with my CEL on and they would still test my car and pass it if it was clean.

Some other States and Provinces have their own criteria.

['97ventureowner]

Originally Posted by johnholl

Can the code erasure function on the OBD II readers help a car pass these crazy emissions systems \ inspections? My state has recently adopted this test on all vehicles post 1996. Money grab, in my opinion. It's the older, exempt cars that are poluting. These emmision parts are very expensive, and should be covered by the manufacturer. In many cases it's a very costly hit or miss replacement proceedure, with respect to the components, and if the mechanic doesen't properly interperate the data correctly, it can cost an arm and a leg. Can you tell I'm pissed?

FYI: I see you live in NY like me, and according to these new emission laws, if you clear the codes, and then go for the inspection, you will get a "vehicle not ready," and have to come back. They will want you to drive the vehicle more so the monitors can run their tests. Then you can bring it back, and it is up to the garage if they want to charge you a re-inspection fee. There apparently seems to be a problem with a lot of people failing the inspection the first time because their vehicles weren't ready. The state DMV has issued a pamphlet concerning this and it should be available at inspection stations soon as well as their website.