OBD codes - 02S and EVAP not ready

[Wing Commander]

I am after some help in diagnosing the codes from my Saab 9000.

I have just bought a U480 OBD scanner/reader and have plugged it in as per the instructions, ie the engine is off but ignition is on. I don't get any DTC codes come up but I get two I/M codes. These are "02S not ready" and "EVAP not ready".

What does this mean? The handbook says that "not ready" means that the monitor has not finished its diagnostic testing, but this seems odd as the scan has completed.

Would it be caused by the car being cold each time I test it? Or is it because the 02 sensor isn't currently in use (because the engine is off) so it gives a weird result?

Any guidance would be great - thanks!

[Wing Commander]

Thanks! That is really useful Confirmed my initial thoughts but this is a new, black art to me!

I presume you mean I run the car at 40ish with a warm engine, then pull over, turn engine off and then test?

It says I shouldn't use the reader with the engine running - hence my thinking.

Thanks again!

[Wing Commander]

Me again - I took the car out for a 30 min run so the car was thoroughly warmed up. The run was between 40 and 60 mph for at least 10-15 minutes so that should have given the car a good amount of opportunity to clear both the 02s and evap "not ready" codes.

I cleared the codes before I set off, and rescanned when I got home. Unfortunately they are still on there.

Could this mean the 02 sensor is on the way out??

Thanks

[Wing Commander]

Thanks once again

I assume it is a non-intrusive test as its just a boggo reader from internet land (U480)

I will run it up tomorrow and see if I can get a different result with the engine running.

[Wing Commander]

Haven't had a chance to give the car a test whilst on the run but did do a test after the car has warmed up. Still had the same results for both the 02s and EVAP.

Arse