Smog Test MIL Fail

[tmikes]

97 mountaineer 5.0 V8 California smog, Fail smog test do to MIL/CHECK ENGINE light to successfully complete all OBD self tests. Do I need a new PCM ? The check engine light is not even on

 

[chefduane]

I think the test can read Pending Codes along with existing codes that will light the CE light. Get an OBDII reader and check for pending codes. Then reset >all< codes just before going to the test location.

 

[ThreeJs]

I think the test can read Pending Codes along with existing codes that will light the CE light. Get an OBDII reader and check for pending codes. Then reset >all< codes just before going to the test location.

If resetting just before the test you will probably get a not ready status. It needs to be drive cycled after clearing all the codes.

 

[chefduane]

If resetting just before the test you will probably get a not ready status. It needs to be drive cycled after clearing all the codes.

Hmm... I guess I'm not sure then what the reader at the test facility really reads. I have been getting a P0455 Pending code (evap system leak) for sometime now and it regularly pops up on my UltraGuage. I just reset it and it goes away for a few weeks. I had my car inspected for registration purposes on Monday and reset the OBDII just before I went in. Passed clean as a whistle with no existing or pending codes, and no 'not ready' status mentioned. No drive cycle reset required. Am I missing something here?

 

[tmikes]

ya I disconnected the battery before I went. Plus I drive on the freeway for a 100 miles and still not pass. What does the drive cycled consist of ? The guy said to drive around for awhile.

 

[D.R.Ball]

Pull the codes ,do not disconnect the battery the code will still be in the system...Use a code scanner, fix the problem and then clear the codes...Also if you just disconnected the battery it takes a while for the engine to reset. But if the OBDII finds a fault it will record the code again.

 

[gatzdon]

Use ForScan to pull all the extended codes. You should be able to see the status of all the monitoring tests to see which one is either failing, or failing to complete.

Completion of all the Evap monitoring tests are not required to clear the P1000 code.

In Illinois and most other states, I believe the state will pass you even if the Evap Monitoring Tests have not completed as long as the P1000 code is cleared, but you need to make sure that is correct for your state based on your model year.

 

[Mike65]

I had a similar problem with our 99 Sport, I replaced an O2 sensor for the CEL & then cleared the code. Drove the truck for one day & took it to state inspection & 3 of the drive monitors were reading not ready. In NJ 2 or less drive monitors not ready will pass. I tested the battery & it was low, replaced the battery & drove it for one day & when I checked it again with my scanner all the drive monitors read ready & it then passed NJ state inspection.

 

[tmikes]

got a OBDII reader finally and everything checks out alright. All I had to do was drive it for a little bit longer Thanks for all the info