auto computer 'trouble codes'

[BigWill]

suppose your "check engine" light is on.

Suppose that whatever code that turns it on is cleared immediately before an inspection.

Would the inspector be able to detect that the code was cleared immediately prior to inspection? Does the computer store that sort of info?

'96 Ford Ranger BTW.

 

[Horns11]

I doubt it. It's not one of the things they check for in inspection.

 

[CottonEyedHorn]

Sounds like if the error is cleared you are good to go.
The Link

 

[accuratehorn]

That is not correct, at least the way Austin does the inspections. The inspection station plugs a computer into the OBDII plug, on all 96 and newer cars (standard plug on all models).
The computer not only detects codes, but also checks the "readiness monitors." These are inputs that tell the computer if the automobile ECM has had enough time or "trips" to tell if the the system is being monitored enough to detect a code if there may be something wrong with that system. There are seven or eight readiness monitors, and all but one or two, depending on the year of the car, have to be functioning for the car to pass inspection.
It usually takes two or more drive cycles, trips with varying speeds usually requiring 15 to 30 minutes of time, for the monitors to reset.
When you erase the codes, it erases the ECM's memory, and it takes some driving for the thing to monitor all the systems again. You can't just erase the code and have the car pass the emissions inspection.
Now, some problems are intermittent, and if you can drive enough to reset the readiness monitors without the code coming back on, and then you get it inspected, it will pass.
Or you could just repair the problem so the car won't be polluting the air, which is the intent of requiring an emissions inspection.

 

[Longhorny630]

bingo, wont work. thought about it myself but the system has to be put through its paces before it will give an all clear