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S-10 & Blazer 1982-2005
The S-10 and Blazer was arguably the most versatile and accessorizable mid-size truck and SUV on the market.
Platform: S/T-series & GMT 330

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  #1  
Old 12-30-2008, 04:52 PM
 
Join Date: Dec 2008
Posts: 4
Default COMPUTER RESET????

I went down to get my 2002 sonoma smogged today. I was told that the computer needed time to reset because I just replaced a few sensors. He said that I had to drive it so many miles for the computer to recognize the changes before I could smog it. He said that it could be anywhere from 20 miles to 400 miles for the computer to reset itself. He said that unless I had a scanner I would not be able to know when it was ready. Has anyone heard of such a thing, that you have to drive so many miles just to be able to smog your vehicle after repairs? My tags are expired (cause i got to get smogged) so I cant really drive around too much. I have left it on idle in my drive way for about half an hour. Think that might work...I'll find out i guess. ANyone have any info on how long it will take until the computer resets? Thanks!
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  #2  
Old 12-30-2008, 09:44 PM
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Default RE: COMPUTER RESET????

They are called the "readiness monitors".The computer must see various thing happen before they become ready. Some examples are must cruise at say 55mph for 3 minutes with out touching the brakes. Must see a decel from 60 to 30 without touching the brakes. Every manufacture is different and there are many things that must happen to bring all monitors online. These things happen with regular driving, depending on how you drive and where you drive is how long it may take, In the state of maryland they give you an extension when you fail to give you time to fix it. If you search on the internet forsonoma readiness monitor reset procedure you may find it . I will try to remember to look on my computer at work tomorrow and I could fax it to you if have a fax but with this being a holiday week we close at 2:00 and are not open on thursday I may not have much time. Idling it in your driveway will not reset them.
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  #3  
Old 01-07-2009, 11:10 AM
 
Join Date: Dec 2008
Posts: 4
Default RE: COMPUTER RESET????

Ok, so apparently it is somewhere between 10 and 100 miles. After getting denied by the smog shop, I drove it 100 miles on 4 seperate trips (about 25 miles acah time). The computer was ready to perfor the smog check. Hope this helps somebody.
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  #4  
Old 01-07-2009, 05:12 PM
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Default RE: COMPUTER RESET????

Its called an OBD II Drive Cycle. its not a matter of how many miles you drive, but like MDTAHOE stated, its a matter of accelerating and decelerating properly. The exact procedre is below

An OBD Drive Cycle:
After you've "fixed" an emissions problem on your OBDII-equipped vehicle, you should perform what's called an "OBDII drive cycle." The purpose of the OBDII drive cycle is to run all of the onboard diagnostics. The drive cycle shold be performed after you've erased any trouble codes from the PCM's memory, or after the battery has been disconnected. Running through the drive cycle sets all the system status "flags" so that subsequent faults can be detected.
The OBDII 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).
NOTE: The ignition key must not be on prior to the cold start otherwise the heated oxygen sensor diagnostic may not run.
[*]As soon as the engine starts, idle the engine in drive for two and a half minutes with the A/C and rear defrost on. OBDII checks oxygen sensor heater circuits, air pump and EVAP purge.[*]Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle. OBDII checks for ignition misfire, fuel trim and canister purge.[*]Hold at a steady state speed of 55 mph for three minutes. OBDII monitors EGR, air pump, O2 sensors and canister purge.[*]Decelerate (coast down) to 20 mph without braking or depressing the clutch. OBDII checks EGR and purge functions.[*]Accelerate back to 55 to 60 mph at throttle. OBDII checks misfire, fuel trim and purge again.[*]Hold at a steady speed of 55 to 60 mph for five minutes. OBDII monitors catalytic converter efficiency, misfire, EGR, fuel trim, oxygen sensors and purge functions.[*]Decelerate (coast down) to a stop without braking. OBDII makes a final check of EGR and canister purge.[/ol]
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  #5  
Old 03-10-2011, 01:33 PM
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Join Date: Mar 2011
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Default My first dumb question of the day...

I just replaced the gas cap after the dreaded P0455 code, but did not clear the code (I had the AutoZone guy read it since he didn't trust me to bring it back...).

How long should I expect the CEL to stay on until I should reasonably consider one of the other problems that P0455 covers?

Is it better to just disconnect the positive terminal for 10 seconds and be done with it, or let the computer find out for itself?
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  #6  
Old 03-12-2011, 12:40 AM
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Ok, I have one better for you. 96 Blazer 4.3L 4X4 go to get inspected. 5 monitors not ready - FAIL. Said to drive around a while and try again. Again, FAIL! Hook OBDII to it and drive it around. all monitors ready. Stop truck, restart, 5 not ready!! I replaced the computer because it was the original with the grounding problem. Any thoughts on how the computer is not staying on? I have heard about the KAM, but cannot locate any info on same online. I have it in the shop, but don't want to pay out my rear for diagnosis if some one here can help.
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  #7  
Old 07-07-2011, 03:24 PM
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Quote:
Originally Posted by shawnvw View Post
Its called an OBD II Drive Cycle. its not a matter of how many miles you drive, but like MDTAHOE stated, its a matter of accelerating and decelerating properly. The exact procedre is below

An OBD Drive Cycle:
After you've "fixed" an emissions problem on your OBDII-equipped vehicle, you should perform what's called an "OBDII drive cycle." The purpose of the OBDII drive cycle is to run all of the onboard diagnostics. The drive cycle shold be performed after you've erased any trouble codes from the PCM's memory, or after the battery has been disconnected. Running through the drive cycle sets all the system status "flags" so that subsequent faults can be detected.
The OBDII 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).
NOTE: The ignition key must not be on prior to the cold start otherwise the heated oxygen sensor diagnostic may not run.
[*]As soon as the engine starts, idle the engine in drive for two and a half minutes with the A/C and rear defrost on. OBDII checks oxygen sensor heater circuits, air pump and EVAP purge.[*]Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle. OBDII checks for ignition misfire, fuel trim and canister purge.[*]Hold at a steady state speed of 55 mph for three minutes. OBDII monitors EGR, air pump, O2 sensors and canister purge.[*]Decelerate (coast down) to 20 mph without braking or depressing the clutch. OBDII checks EGR and purge functions.[*]Accelerate back to 55 to 60 mph at throttle. OBDII checks misfire, fuel trim and purge again.[*]Hold at a steady speed of 55 to 60 mph for five minutes. OBDII monitors catalytic converter efficiency, misfire, EGR, fuel trim, oxygen sensors and purge functions.[*]Decelerate (coast down) to a stop without braking. OBDII makes a final check of EGR and canister purge.[/ol]
what if i live abt 2 miles from the freeway? I will not be able to drive 55 to 60 mph on the side streets.
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  #8  
Old 12-23-2011, 11:34 PM
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Join Date: Dec 2011
Posts: 2
Default

Donesha88: you don;t want to try and clear your monitor on the freeway. you need to slow down to 20mph and the truckers don;t like that. I found a long little used road out in the Mojave desert I used. my problem was getting a cold start out there, I left my truck set for a couple of hours to cool off, then did the cold start thing. to be honest I still have some of the monitors cleared, but still have two that won.t, still working on it.
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  #9  
Old 01-18-2012, 09:37 AM
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Quote:
Originally Posted by shawnvw View Post
Its called an OBD II Drive Cycle. its not a matter of how many miles you drive, but like MDTAHOE stated, its a matter of accelerating and decelerating properly. The exact procedre is below

An OBD Drive Cycle:
After you've "fixed" an emissions problem on your OBDII-equipped vehicle, you should perform what's called an "OBDII drive cycle." The purpose of the OBDII drive cycle is to run all of the onboard diagnostics. The drive cycle shold be performed after you've erased any trouble codes from the PCM's memory, or after the battery has been disconnected. Running through the drive cycle sets all the system status "flags" so that subsequent faults can be detected.
The OBDII 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).
NOTE: The ignition key must not be on prior to the cold start otherwise the heated oxygen sensor diagnostic may not run.
[*]As soon as the engine starts, idle the engine in drive for two and a half minutes with the A/C and rear defrost on. OBDII checks oxygen sensor heater circuits, air pump and EVAP purge.[*]Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle. OBDII checks for ignition misfire, fuel trim and canister purge.[*]Hold at a steady state speed of 55 mph for three minutes. OBDII monitors EGR, air pump, O2 sensors and canister purge.[*]Decelerate (coast down) to 20 mph without braking or depressing the clutch. OBDII checks EGR and purge functions.[*]Accelerate back to 55 to 60 mph at throttle. OBDII checks misfire, fuel trim and purge again.[*]Hold at a steady speed of 55 to 60 mph for five minutes. OBDII monitors catalytic converter efficiency, misfire, EGR, fuel trim, oxygen sensors and purge functions.[*]Decelerate (coast down) to a stop without braking. OBDII makes a final check of EGR and canister purge.[/ol]
TO SHAWNW: Is this the same procedure for a 96 jimmy? If not do u know where I can find the procedure to reset the readiness monitor. Not knowing, I changed the battery just days before I took it to be inspected, I've drove it over 500 miles, put more than $150 in fuel & when I put it on the scanner I still have 4 remaining. PLEASE HELP!
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Old 01-18-2012, 09:37 AM
 
 
 
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camaro, cobalt, codes, computer, corvette, cycle, drive, ii, jump, long, miles, obd, readiness, reset, starting


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