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Discussion Starter · #1 ·
Ok I have a situation. My 2001 Impala Base has been sitting up for about 2-3 yrs. We finally got it up & running but their is one problem- we keep failing the Emissions test because they say the computer is not ready. The 1st time we said ok and drove it around for about 3weeks. We got up to 100 miles and then the Check Engine light popped on. We took care of that- it was just the O2 Sensor for the Catalytic converter. So after we fixed that we had about 188miles on it. We took it to get another emissions test and it failed again. The test said we failed only because It's still not ready. What is the problem?? Around what time or how many miles will the computer cut back on and be ready?? Somebody help me PLEASE!!!!!!!!!!!!!!!!!!!!!!!!!:WTF::gaah::bang:
 

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ummm wtf do they mean by computer not ready?
if the pcm isnt ready... youre car shouldnt be running lol

if you have a printout of the test, plz scan and attach. + emissions guidelines would help, but Ive never heard of a computer being "not ready"
 

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OBD-II computers are not emission test ready until it completes it self diagnostic check of all emission components during its "Drive Cycle". Certain conditions must be met before the PCM will read that it is "Emission Compliant".

To the OP, try this:

RUNNING AN OBD-II DRIVE CYCLE
The purpose of completing an OBD II drive cycle is to force the vehicle to run its onboard self testing diagnostics. Some form of a drive cycle needs to be performed after DTCs have been erased from the PCM’s memory or after the battery has been disconnected. Running through a vehicle’s complete drive cycle will “set” the readiness monitors so that future faults can be detected (and potentially to pass the emissions inspection). Drive cycles vary depending on the vehicle and the monitored items that needs to be re-set. Whenever possible, follow the drive trace prescribed for the specific vehicle/monitor in question. Some vehicle-specific drive cycles can be found in the vehicle’s Owner’s Manual.
The following “universal” drive cycle can be used as a guide to assist with re-setting monitors when a vehicle specific drive cycle cannot be located. This generic OBD-II drive cycle begins with a cold start (coolant temperature below 122 degrees F and the coolant and air temperature sensors within 11 degrees of one another). This condition can be achieved by allowing the vehicle to “sit” overnight, and then by beginning the drive cycle the next day. Most drive cycles will be difficult to follow exactly under normal driving conditions, so the driver should exercise caution, road safety, and courtesy to others.
• Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on.
• Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle.
• Hold at a steady speed of 55 mph for three minutes.
• Decelerate (coast down) to 20 mph without braking or depressing the clutch.
• Accelerate back to 55 to 60 mph at ¾ throttle.
• Hold at a steady speed of 55 to 60 mph for five minutes.
• Decelerate (coast down) to a stop without braking.
 

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OBD-II computers are not emission test ready until it completes it self diagnostic check of all emission components during its "Drive Cycle". Certain conditions must be met before the PCM will read that it is "Emission Compliant".

To the OP, try this:

RUNNING AN OBD-II DRIVE CYCLE
The purpose of completing an OBD II drive cycle is to force the vehicle to run its onboard self testing diagnostics. Some form of a drive cycle needs to be performed after DTCs have been erased from the PCM’s memory or after the battery has been disconnected. Running through a vehicle’s complete drive cycle will “set” the readiness monitors so that future faults can be detected (and potentially to pass the emissions inspection). Drive cycles vary depending on the vehicle and the monitored items that needs to be re-set. Whenever possible, follow the drive trace prescribed for the specific vehicle/monitor in question. Some vehicle-specific drive cycles can be found in the vehicle’s Owner’s Manual.
The following “universal” drive cycle can be used as a guide to assist with re-setting monitors when a vehicle specific drive cycle cannot be located. This generic OBD-II drive cycle begins with a cold start (coolant temperature below 122 degrees F and the coolant and air temperature sensors within 11 degrees of one another). This condition can be achieved by allowing the vehicle to “sit” overnight, and then by beginning the drive cycle the next day. Most drive cycles will be difficult to follow exactly under normal driving conditions, so the driver should exercise caution, road safety, and courtesy to others.
• Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on.
• Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle.
• Hold at a steady speed of 55 mph for three minutes.
• Decelerate (coast down) to 20 mph without braking or depressing the clutch.
• Accelerate back to 55 to 60 mph at ¾ throttle.
• Hold at a steady speed of 55 to 60 mph for five minutes.
• Decelerate (coast down) to a stop without braking.
Just to add, this can take several days or several hundred miles of driving. Usually the Catalyst ready monitor is the last one to come online. I dont know about your emissions tests but many states allow some wiggle room and will pass the vehicle with one or two monitors not ready. I live in NW Indiana and ours will allow you one monitor not ready. Drive it for a few days, stop by your local auto zone or advance auto or whatever you have in your area and ask them to do a scan to see if the monitors are all set and ready before visiting the emissions testing site again.
 

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Discussion Starter · #6 ·
Thanks tto all! Sorry about the late response I wasnt online for a few days but I will try these things and let you all know how they turn out
 

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stupid emissions test :p
I won't argue that with you, thank our legislators. I live in NW Indiana, we have Interstate 80 right in our back yard along with several large industries. All of that combined does more damage to the air than all of the local residents vehicles put together, but we're the ones who get screwed.
 

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Actually if you look at the figures for sources of air pollution, cars are pretty insignificant. We could all be driving busses and it would hardly make a difference. Farms and factories are the big polluters, but for some reason cars take the blame.
 

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Actually if you look at the figures for sources of air pollution, cars are pretty insignificant. We could all be driving busses and it would hardly make a difference. Farms and factories are the big polluters, but for some reason cars take the blame.
not for some reason, its bec libs dont want u driving at all, they want everyone taking mass transit
 

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Discussion Starter · #10 ·
Quick Update- We finally got he system test done & the computer started reading. Now the downfall of it is- I have to replace my catalytic converter
 

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Quick Update- We finally got he system test done & the computer started reading. Now the downfall of it is- I have to replace my catalytic converter
Did you follow the steps above or just drive normal for a few days and the monitors reset?

I have an '02 failing emissions because of EVAP and o2 sensor heater not online yet.
 

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Discussion Starter · #12 ·
We drove it normally and then the Check Engine light popped back on. We got the codes read and it was the Catalytic Converter that was bad
 

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I have an 02 impala and the same evaporative and cat aren't ready yet. I bought a new cat and battery. About 100 miles later still nothing. I barely started warming it up the way mentioned today. I will continue to do so and what happens.
 

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Mr. Handy
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Cat code/o2 sensor is last one to complete it's test by the PCM as said before. Mine took 200mi or so after replacing my cat.

You will also notice your transmission slipping during this period of time. If it is don't worry it will go away.
 

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my 2010 Impala is doing that , but i have done GM'S drive cycle 3 times and have drove over 100 miles..no check engine light and STILL NOT READY.. evap and o2...
 

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Well I am having a similar issue. I am on COLORADO and I have been to the Emission Test place twice and both time I have Readiness Monitors "INC" aka .. Not Ready. They are "Evaporative" and "Oxygen Sensor".
Never had this happen before in 7 years of ownership.
Other Info:
2013 Impala LTZ 3.6 with FlexFuel
114700 Miles.
I have an OBD Reader .. A Foxwell NT200. Works just fine as far as I can tell.
No Check Engine Lights .. at all.
I have been having an intermittent Check Engine Light for Gas Cap for the last six months. I cleared Check Engine Lights with my OBD Reader about 3 weeks ago before my first try at the Smog place. None have popped up since then.
I purchased and a new OEM gas cap and have that in place now.. about 2 days ago.
I replaced the EVAP Purge Valve about 9 month (2000 miles) ago. Second time I have done this in 7 years.

There are a couple posts here that discuss the "drive cycle" to get "ready". But those descriptions are generic as far as I can tell. Discussion of how far to drive, speeds, how full is the tank.. etc. Does anyone here know where I can find the spec. shows the exact Drive Cycle requirements for my Vehicle?

And any other ideas of how to get the system ready? i have a couple weeks to fuss with it if necessary... Really don't want to spend the money to take to a shop if it is something fairly straight forward.

Thanks in advance for any help.
 

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OBD-II computers are not emission test ready until it completes it self diagnostic check of all emission components during its "Drive Cycle". Certain conditions must be met before the PCM will read that it is "Emission Compliant".

To the OP, try this:

RUNNING AN OBD-II DRIVE CYCLE
The purpose of completing an OBD II drive cycle is to force the vehicle to run its onboard self testing diagnostics. Some form of a drive cycle needs to be performed after DTCs have been erased from the PCM’s memory or after the battery has been disconnected. Running through a vehicle’s complete drive cycle will “set” the readiness monitors so that future faults can be detected (and potentially to pass the emissions inspection). Drive cycles vary depending on the vehicle and the monitored items that needs to be re-set. Whenever possible, follow the drive trace prescribed for the specific vehicle/monitor in question. Some vehicle-specific drive cycles can be found in the vehicle’s Owner’s Manual.
The following “universal” drive cycle can be used as a guide to assist with re-setting monitors when a vehicle specific drive cycle cannot be located. This generic OBD-II drive cycle begins with a cold start (coolant temperature below 122 degrees F and the coolant and air temperature sensors within 11 degrees of one another). This condition can be achieved by allowing the vehicle to “sit” overnight, and then by beginning the drive cycle the next day. Most drive cycles will be difficult to follow exactly under normal driving conditions, so the driver should exercise caution, road safety, and courtesy to others.
• Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on.
• Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle.
• Hold at a steady speed of 55 mph for three minutes.
• Decelerate (coast down) to 20 mph without braking or depressing the clutch.
• Accelerate back to 55 to 60 mph at ¾ throttle.
• Hold at a steady speed of 55 to 60 mph for five minutes.
• Decelerate (coast down) to a stop without braking.

And just then, at that exact time your car comes to a complete stop on the highway you were just doing 60MPH, a log-hauling 18 wheeler accelerates your car from 0 to 70 in 55 milliseconds causing you to pull approximately 2700G and the trunk of your car to be in front of the engine block, while some of your remains are oozing past the O2 sensor inside your muffler. It is NEVER 100% to come to a complete stop on a highway and it illegal and unsafe to do 60mph in a school zone, where 20 miles per hour would be ok. Another scenario might be as you are slowing down from 60 to 0 on the highway, some aggravated guy with a beard pulls out his shot gun and road rages on you!
 
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