Failing Inspection Please Help
CF Beginner
Joined: Apr 2012
Posts: 1
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Nice
Just found this little chart that confirms my suspician....
System Status and Drive Cycle For Satisfying the Federal Inspection/Maintenance (I/M 240) Regulations
The system status selection is included in the scan tool System Info menu.
Several states require that the I/M 240 (OBD ll system) pass on-board tests for the major diagnostics prior to having a vehicle emission inspection. This is also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the system status, complete or not complete, in order to verify that the vehicle meets the criteria which complies with local area requirements. Using the system status display, any of the following systems or a combination of the systems may be monitored for I/M readiness:[align=left]•
The catalyst[/align][align=left]•
The HO2S[/align][align=left]•
The HO2S heater[/align]
Important:The system status display indicates only whether or not the test has been completed. The system status display does not necessarily mean that the test has passed. If a Failed Last Test indication is present for a DTC associated with one of the above systems, that test is failed. Diagnosis and repair is necessary in order to meet the I/M 240 requirement. Verify that the vehicle passes all of the diagnostic tests associated with the displayed system status prior to returning the vehicle to the customer. Refer to the Typical OBD II Drive Cycle table to use as a guide to complete the I/M 240 system status tests. More than one drive cycle may be needed.
Following a DTC info clear, the system status will clear only for the systems affected by any DTCs stored. Following a battery disconnect or a control module replacement, all of the system status information will clear.
Typical OBD II Drive Cycle
Diagnostic Time Schedule for I/M Readiness
Vehicle Drive Status What is Monitored?
Cold Start, coolant temperature less than 50°C (122°F) --
Idle 2.5 minutes in Drive (Auto) Neutral (Man), A/C HO2S Heater, Misfire, Secondary Air, Fuel Trim, EVAP Purge
and rear defogger ON
A/C off, accelerate to 90km/h (55mph), 1/2 throttle. Misfire, Fuel Trim, Purge
3 minutes of Steady State - Cruise at 90km/h (55mph) Misfire, EGR, Secondary Air, Fuel Trim, HO2S, EVAP Purge
Clutch engaged (Man), no braking, decelerate to 32km/h (20mph) EGR, Fuel Trim, EVAP Purge
Accelerate to 90-97km/h (55-60mph), 3/4 throttle Misfire, Fuel Trim, EVAP Purge
5 minutes of Steady State Cruise at 90-97km/h (55-60mph) Catalyst Monitor, Misfire, EGR, Fuel Trim, HO2S, EVAP Purge
Decelerate, no breaking. End of Drive Cycle EGR, EVAP Purge
Total time of OBD II Drive Cycle 12 minutes
System Status and Drive Cycle For Satisfying the Federal Inspection/Maintenance (I/M 240) Regulations
The system status selection is included in the scan tool System Info menu.
Several states require that the I/M 240 (OBD ll system) pass on-board tests for the major diagnostics prior to having a vehicle emission inspection. This is also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the system status, complete or not complete, in order to verify that the vehicle meets the criteria which complies with local area requirements. Using the system status display, any of the following systems or a combination of the systems may be monitored for I/M readiness:[align=left]•
The catalyst[/align][align=left]•
The HO2S[/align][align=left]•
The HO2S heater[/align]
Important:The system status display indicates only whether or not the test has been completed. The system status display does not necessarily mean that the test has passed. If a Failed Last Test indication is present for a DTC associated with one of the above systems, that test is failed. Diagnosis and repair is necessary in order to meet the I/M 240 requirement. Verify that the vehicle passes all of the diagnostic tests associated with the displayed system status prior to returning the vehicle to the customer. Refer to the Typical OBD II Drive Cycle table to use as a guide to complete the I/M 240 system status tests. More than one drive cycle may be needed.
Following a DTC info clear, the system status will clear only for the systems affected by any DTCs stored. Following a battery disconnect or a control module replacement, all of the system status information will clear.
Typical OBD II Drive Cycle
Diagnostic Time Schedule for I/M Readiness
Vehicle Drive Status What is Monitored?
Cold Start, coolant temperature less than 50°C (122°F) --
Idle 2.5 minutes in Drive (Auto) Neutral (Man), A/C HO2S Heater, Misfire, Secondary Air, Fuel Trim, EVAP Purge
and rear defogger ON
A/C off, accelerate to 90km/h (55mph), 1/2 throttle. Misfire, Fuel Trim, Purge
3 minutes of Steady State - Cruise at 90km/h (55mph) Misfire, EGR, Secondary Air, Fuel Trim, HO2S, EVAP Purge
Clutch engaged (Man), no braking, decelerate to 32km/h (20mph) EGR, Fuel Trim, EVAP Purge
Accelerate to 90-97km/h (55-60mph), 3/4 throttle Misfire, Fuel Trim, EVAP Purge
5 minutes of Steady State Cruise at 90-97km/h (55-60mph) Catalyst Monitor, Misfire, EGR, Fuel Trim, HO2S, EVAP Purge
Decelerate, no breaking. End of Drive Cycle EGR, EVAP Purge
Total time of OBD II Drive Cycle 12 minutes
CF Beginner
Joined: Jun 2025
Posts: 1
Likes: 0
Failing emissions after a 5 to 1 gas analyzer has passed your vehicle,
1997 Chevy S-10. I keep failing for my OBD Emissions. The readiness Status for just about everything, Cats, Ox sensors, EGR, Evap. The guy at inspection told me its not that there is anything wrong with those systems just that the computer is not reading them. i had the comp put on a machine at my local mechanic and everything came up fine. Went back to inspection and they all came up again, this time they told me there is nothing they can do as long as it comes up they cant pass me. Please anyone have any ideas of what could be wrong.
Thanks
Thanks
This type of emissions failure is to be more associated with either a leaking evap system failure ie. Gas cap, or after a fuel pump replacement without using the new gasket(s) or improperly installing the components the faulty evap should have a code. While a leaking gasket may not have a evap code.
Also the ground battery terminal has a ground wire to the body this is important for your map sensor, also check the left side lower frame main ground. Voltage drop testing will show a problem when almost all other tests fail...
Hope this helps
Also the ground battery terminal has a ground wire to the body this is important for your map sensor, also check the left side lower frame main ground. Voltage drop testing will show a problem when almost all other tests fail...
Hope this helps
Last edited by Steven357; Jun 25, 2025 at 1:56 PM.
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