What causes a vehicle to *not* pass an emissions test?

Posted by admin on June 29th, 2009 and filed under emissions test |

Would a need for an oil change? Also my check engine light is on (haven't been able to afford to get in, driving minimally) would that effect the emissions at all? I have a 99 Chevrolet Cavilier, with higher mileage. Thank you in advance!

I am aware it is an exaust test. Here in Washington it's manditory to renew my tabs.

I don't know about Washington but in Ohio for cars 96 and newer they hook the car up to a scan tool so if your check engine light is on or if it does not work you fail. Any reason your check engine light goes on is emission related. It is a federally regulated system so the governmant can keep tabs on emissions. They do this by requiring car manufacturers to monitor emissions through various sensors. When a reading is too high or low it causes the check engine light to come on. There are hundreds of reasons why the PCM will turn the check engine light on. If you need to take a tailpipe emissions test I need to know what gas failed (HC, CO, or NOx) to tell you what may be wrong. If it is the diagnostic test I need to know what codes are stored in the computer to tell you what may be wrong.

3 Responses

  1. silverblack12345 Says:

    Most check engine lights are related to the exhaust system and emissions control. I would be willing to bet that your manual (if you still have it) would say the same. You may just need your fuel injectors cleaned or something minor like that. Get an oil change and also buy a bottle of fuel injection cleaner which is like 2 bucks, and pour it in the gas tank before your next fill up. If that doesn't work, then it's time to head to a mechanic. Also, auto zone will hook up a machine for free, and tell you what the error code means with the check engine light.
    References :

  2. jose_valle76 Says:

    just for having check engine light on will fail test,for emission testing,give full tune up and then after fixing all the above take and get it tested.good luck!
    References :

  3. acmeroadrunner2003 Says:

    I don't know about Washington but in Ohio for cars 96 and newer they hook the car up to a scan tool so if your check engine light is on or if it does not work you fail. Any reason your check engine light goes on is emission related. It is a federally regulated system so the governmant can keep tabs on emissions. They do this by requiring car manufacturers to monitor emissions through various sensors. When a reading is too high or low it causes the check engine light to come on. There are hundreds of reasons why the PCM will turn the check engine light on. If you need to take a tailpipe emissions test I need to know what gas failed (HC, CO, or NOx) to tell you what may be wrong. If it is the diagnostic test I need to know what codes are stored in the computer to tell you what may be wrong.
    References :

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