Focus Fanatics Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
54 Posts
Discussion Starter #1
tell me if this makes any sense.

first off my car failed inspection due to a sensor "not ready" check.

now i dont have any DTC stored in my pcm and i dont have a check engine light on.

next there is nothing saying that i have a bad sensor otherwise i would have a dtc right?

also i have not disconnected my battery in over 6 months

well i am up in the air about this one so if anyone has any idea that would be great.
 

·
Registered
Joined
·
3,737 Posts
"READINESS ISSUES

One of the EPA's requirements for using a plug-in OBD II check in lieu of a tailpipe test is to make sure the OBD II system has run all of its monitors and that the monitors have all passed. But there's a catch. Some import vehicles have readiness issues when it comes to setting all the OBD II monitors. Consequently, the EPA currently allows up to two readiness monitors not to be set prior to testing 1996 to 2000 model-year vehicles, and one readiness monitor for 2001 to 2003 vehicles.

When OBD II runs a self-check on a particular component or system, it lets you know by setting a readiness "flag" or indicator, which can be displayed on your code reader or scan tool. If OBD II has run all the available monitors and all the monitors have passed - and no faults have been found - the vehicle should pass the OBD II plug-in test. But if all the required monitors have not run, the vehicle can't be given an OBD II test. The motorist must drive the vehicle and come back again, or take a tailpipe test if that is an option.

If OBD II detects a fault when running a monitor, the setting of a code may prevent the remaining monitors from running. A bad oxygen sensor, for example, will prevent the catalyst monitor from running. Getting all the monitors to run can be tricky on some vehicles. Each monitor has certain operating requirements that must take place before the self-check will run.

To set the converter monitor, for example, the vehicle may have to be driven a certain distance at a variety of different speeds. The requirements for the various monitors can vary considerably from one vehicle manufacturer to another, so there is no "universal" drive cycle that will guarantee all the monitors will be set and ready.

Mike Cole of the National Center for Vehicle Emissions Control and Safety (NCVECS) at Colorado State University says some vehicles require very specific drive cycles (called "drive traces" if you perform them on a road simulator or dyno) to activate certain self-checks like the catalyst and EVAP monitors. NCVECS has compiled all the known drive traces for various vehicles on a CD and offers the package to technicians for about $40. For more information, you can visit www.ncvecs.colostate.edu.

As a general rule, doing some stop-and-go driving around town at speeds up to about 30 mph, followed by five to seven minutes of steady 55 mph highway speed driving, will usually set most or all of the monitors. Consequently, if you're checking an OBD II system and discover that one or more of the monitors have not run, it may be necessary to test-drive the vehicle to set the remaining monitors.

With the EVAP monitor, the vehicle may require a certain period of inactivity (such as sitting overnight) and certain ambient temperature conditions (such as above freezing) before the EVAP monitor will run."

http://www.aa1car.com/library/2004/ic50452.htm

A further google search should give you some more advice about what type of "cycle" to drive your car through to make sure all the readiness indicators are set.
 

·
Registered
Joined
·
1,067 Posts
The reason they will fail you for that, is people will try to clear their codes right before testing, to try to trick the testing center.

Do what Penguin says, drive the car for a few miles in town and at least two highway drives (above 50)for over 10 minutes each time, and you should bave gotten through all your drive cycles
 

·
Registered
Joined
·
54 Posts
Discussion Starter #4
i havent cleared my codes in over 2 years
i forgot to reconnect my maf
anyway i got it to pass
we found that the pcm is clearing the ready statis when you key off
so anyway
i will fix it next year
 

·
Registered
Joined
·
25,621 Posts
The reason they will fail you for that, is people will try to clear their codes right before testing, to try to trick the testing center.

^^ Really ?? People do that...say it isn't so...LOL
 
1 - 6 of 6 Posts
Top