Readiness Monitor - FAILED EMMISION


Old 10-30-14, 09:25 AM
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Readiness Monitor - FAILED EMMISION

This is completely ridiculous and I am having trouble trying to understand this!

I had check engine light. Coolant problem. I replaced a thermostat and sensor and all is fine with the vehicle. During my repair I disconnected the battery... it also cleared the check engine light.

Later that same day, I took it in for a due emission testing and it bleeping failed!!


How can I reset these? Is it a matter of driving it and it will clear itself? How the heck long does that take?

And to confirm, those sensors have nothing to do with a coolant system does it? I just want to assure my repair or previous problem is not causing this!!
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Old 10-30-14, 10:53 AM
Join Date: Jun 2010
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It would really help if you told us make/model/year of vehicle that you are talking about ....
Old 10-30-14, 11:36 AM
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2008 Chevy Cobalt LS 2.2 .....................
Old 10-30-14, 11:49 AM
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The car has to complete a certain amount of tests/cycles to recalibrate itself. Until that time it won't pass when they put it on the machine. You local dealer/mechanic should be able to tell you how many and what sort of driving you need to do. Surprised the testing station didn't tell you if they knew the work you had done.
Old 10-31-14, 06:08 AM
Join Date: Jun 2013
Location: usa
Posts: 111
I found this cycle.different criteria for each monitor.cant find my book......
General Motors Driving Cycle

A complete driving cycle should perform diagnostics on all systems. A complete driving cycle can be done in under fifteen minutes.

To perform an OBDII Driving cycle do the following:

Cold Start. In order to be classified as a cold start the engine coolant temperature must be below 50C (122F) and within 6C (11F) of the ambient air temperature at startup. Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.
Idle. The engine must be run for two and a half minutes with the air conditioner on and rear defroster on. The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.
Accelerate. Turn off the air conditioner and all the other loads and apply half throttle until 88km/hr (55mph) is reached. During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.
Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for 3 minutes. During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.
Decelerate. Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.
Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.
Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.
Decelerate. This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.
Old 10-31-14, 06:25 AM
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Just to add to Vic's and Autojoe's comments, each vehicle is different in the amount of driving/time/conditions it may take before it's "ready" for testing again. Nothing to do with anything being "wrong", just a computer thing. My truck takes parts of about 2-3 days to finish... I think it's the EVAP that takes the longest to finish testing.

A lot of people try to get around the check engine light problems they have by just disconnecting the battery and trying to make the PCM forget it's codes in an effort to try and pass the testing. So I'm not surprised they didn't tell you. They probably hear that song and dance 10x a day.

You could take it to any autostore and ask them to tell you if it's ready for testing again.
Old 10-31-14, 11:56 AM
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FWIW -- The EVAP (whatever that is?) does not have to pass in my county. So the only thing that stopped me that day (besides stupidity) is the OXYGEN and OXYHEAT.

I think what took me most by surprise I feared I had caused these "failures" by my repair. As far as I can tell neither of these OXYGEN and OXYHEAT have anything to do with a coolant system? As far as I know....

I was feeling real good too... just saved about 5 bills with my 50 dollar repair earlier that morning and then these stinking emission idiots burst my bubble.

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