OBDII problems...

O2 sensors and catalytic converters must be fully warmed up to operating temperature before they send a valid signal to the computer.

Assuming that you do not have a check engine light illuminated, next time you take the vehicle in for an emissions test, take if for a run on the highway for about a half hour to get everything warmed up.

I had the same problem after a computer reset on my truck. It took several days of varied driving to get enough flags to the ready state for a smog test. Luckily I have my own code reader, so I was able to see when I got the minimum amount to the ready state. I performed the prescribed OBDII drive cycle several times to no avail. It just took a lot of varied everyday driving.

I had a similar thing when I changed air filter in the Highlander (02). I had a vacuum hose loose and didn't see it - check engine light came on anyhow for about a week of mixed driving before it reset.

The OP's problem is different. He is not having a problem with his MIL being illuminated. He is referring the emission test readiness indicators that require the use of a personal code reader or the smog shops equipment to see.

take a look here

for the record, I have an F150 that did the exact same thing once and it took over 600 miles of driving to complete all the various cycles. Usually a P1000 code is what causes emissions test to fail. Nothing you can really do except drive in various conditions.

Thanks guys for all of your input. I guess I'll just keep on driving for a while. Does AutoZone have guys that can check the OBDII status for you? Maybe I'll go to them every couple of days.

Also, as mentioned previously, my check engine light is not illuminated.

AutoZone, among other places, have OBD II scanners that you can borrow.

DOES THE CHECK ENGINE LIGHT EVEN WORK?

When you get ready to start the car , the Check Light MUST come on to verify that the light works. The previous owner might have disconnected the light so you or other prospective buyers didn't notice that the light was constantly on.

Good question. It does come on when I start the truck. Also, there are no error codes when reading computer.

??? Then how does it fail smog?

If the sensors report to the smog that they are not ready, they must also report to the car itself that they are not ready. Ray, something sounds wrong here, don't you think?

And, checking the Check light to see if it comes on tells us that the Check light operates.

With 2-trip detection logic, the ECU has to record 2 trips without any problems to be "ready."

The OP should take the car out for a good ride on the highway, at least 30 minutes long, then park the car overnight, and repeat, then get the car good and warmed up before going for an emissions check.

So far I've driven the truck over 400 miles. I went to Autozone last night and had them check it again. The same three sensors are still in Not Ready status. I printed out a basic drive cycle that I found on the internet and ran through it. I'll probably go through it again tonight. A mechanic friend of mine suggested that if I might want to try to get the truck extra hot by placing a piece of cardboard in front of half of the radiator for a few minutes. (Making sure not to over heat the engine). If I haven't mentioned it before, the sensors are the Evap, Catalyst, and the EGR.

Assuming that you did not drive the entire 400 miles in one trip and you parked the truck overnight between a couple of long trips, the ECU should have reset by now. 3 different unrelated sensors makes me think that there is a loose connection somewhere.

Look under the dashboard where the diagnostic connection is, and follow the wire loom back to the next connectors to make sure they are tight. Also check the sensors you mentioned. I think there is more than 1 evap sensor, but check the one on the charcoal canister in the engine compartment, check the sensor next to the EGR valve, and check the #2 O2 sensor after the catalytic converter.

You're right. There have been multiple trips with overnight rests in between. I'll try these things and get back to ya. One question though... If there was a problem with the connection, wouldn't the check engine light come on?

In theory, yes, in reality, no. I'd check to be sure.

There is nothing funny going on. I had the same experience. Two years ago (at biannual smog test time) I had a bad MAF sensor and my MIL was illuminated. After replacing the sensor the computer was reset to clear the error code and reset the MIL. This also clears the emissions readiness monitors. After the repair when I went to pick up the truck, I was told it had not been smogged because there weren't enough monitors showing ready status and that it would fail if attemped. I was told to drive for a while and then come back. It took three days for me to have enough monitiors show ready. They told me that they have had vehicles that took a couple of weeks or more of driving to get enough monitors in ready status to be able to smog. And you won't have a "check engine" light for this.

I thought he had done that. He bought the car and has put over 400 miles on it.

That's odd. It seems to me that the sensors would need to come to ready every time the motor starts so that the computer could do it's job.

This explains monitors well.

My code reader that came in very handy and kept me from driving back and forth to the shop.