SMOG Test - OBDII Monitors Not Ready

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Recently my 2001 Tundra V8, 197K on the ODO, threw 2 codes. Never before...
I used my module and Torque app to clear the codes, to see if they return.
I generally do this... The codes did not return.
It was maybe 30 miles ago.

Took her in for the 2 year SMOG check; it always passes with ease. The truck is perfect.
It failed due to "OBDII Monitors Not Ready", citing Catalyst and Evaporative System.
As I recall, Evap was one of the codes thrown.

The operator told me to drive the vehicle for 1,000 miles to generate some data. "It lost it's memory."
Please offer your experiences.
I appreciate your guidance.
 
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Originally Posted by MarkM66
Does your app not state if the monitors are ready?

Dunno. Gonna check; I was wondering that myself. Thanks.
 
Did you actually fix anything? Or just praying they don't come back?
 
Originally Posted by mattd
Did you actually fix anything? Or just praying they don't come back?

I was diagnosing.
My practice is to clear the codes and see if they return.
In my experience, they come back immeadiately or not at all.
A loose gas cap is a common cause to throw an evap code.
A neighbor recently borrowed our Tundra and gassed it up.
The truck has never thrown a code before.
When they returned it, they said, "Your check light in on."
Due to age, I was thinking an O2 sensor... But it was an evap code error.

So no, I did not fix anything. So far there is nothing to fix.
I don't pray about cars.
 
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100 mile, not 1000. Takes a few drive cycles, some highway, some local.
Every vehicle make should have the specific cycle to get them to set, but most are less than 100 miles.

No idea if the torque app shows if systems are ready, but I would think it would. Even my cheap $10 reader shows the status of Cat, evap, etc.
 
Originally Posted by blupupher
100 mile, not 1000. Takes a few drive cycles, some highway, some local.
Every vehicle make should have the specific cycle to get them to set, but most are less than 100 miles.

No idea if the torque app shows if systems are ready, but I would think it would. Even my cheap $10 reader shows the status of Cat, evap, etc.

Perfect. Thanks. Will do today.
 
It varies by manufacturer and even vehicle model. My Mustang and XTerra will both set all monitors within 15-20 miles and a single warmup, but my old Cavalier required 5 separate warm-up cycles to set the cat monitor.

I've never had a need to check on the Camry, Versa, or Tacoma.

Torque dues show monitor status, under realtime info > emissions readiness
 
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Echo the look up drive cycle. Also look up California smog check requirements for that specific vehicle. Evap is the hardest monitor to set. Engine and outside temp requirements, gas tank has to be between 1/4th and 3/4th filled, etc.etc. On my RAV4 it was so hard to set it was exempted.
Buy an OBD II code reader that will tell you codes and which monitors are set. It will be the best money you ever spent.

Never mind about the OBD reader if Torque provides monitor readiness information. And looking it up online I see evap not ready is acceptable to pass if it is the only monitor not set. I had a Colorado that would fail at the 400 mile point. I would reset the monitors, do a couple of drive cycles, then have it smogged before it completed the test and failed.
 
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Toyota tends to be picky about running certain cycles like the EVAP one, where the car needs to have more than 1/2 tank of fuel and must sit out for more than 6 hours. The EGR, cat and misfire monitors should run on a drive.

I hooked up my Carista reader for laughs and giggles after the parent's Sienna was "brain dead" from a disconnected battery. I noticed some monitors were running when the car was started and I saw a few flick on to complete as the car was driven. Now the Prius, since it does use a bladder fuel tank and a EVAP pump, Toyota wants that car to remain stationary for at least 6 hours so the pump can run and the monitor can check for any leaks beyond a set reference value(in this case, there's a orifice in the EVAP module as a reference "leak").
 
Outstanding contributions.
I appreciate your guidance.

I just drove 35 miles to Menlo Park on the freeway. No check engine light.
I will drive another 50 and fill 'er up.

Kinda like a new adventure.
Dang Tesla don't throw no codes.... Ha!
Kidding; I love this ols Tundra.
 
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Had the same problem a few months ago with a Camry V6. Basically the drive cycles test is to prevent people from resetting the ECU if they have a check engine light.

Those drive cycles are very manufacturing specific. I remember you have to keep the gas tank half instead of full, and drive however many miles, starting (both warm and cold), and however minutes between certain speed. Best to look up how it is online.

Make sure you have a scanner to see if the cycle is done. I remember my smog guy suggested an Autel $35 scanner from Amazon. He said that matches what he sees when he smog.
 
Again, great advice.
Drove about 60 miles, mostly freeway Interstate 280 north then to south valley and filled up at Costco. $3.29 for rag; not bad.
Got Bunni a trinket; Sunday is her birthday and she is amazing. I married up, for sure.
Neighbors gave us tickets to the 9er Steeler game... I wouldn't pay those prices!

Anyway, home and plugged in module and fired up Torque. No check engine light, no codes.
Going in the right direction because catalyst is complete.
But evap still incomplete. I'll try and look up the start/stop requirements.



TundraOBD2_20190920.jpeg
 
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Sheesh...

Begin by: (It is very important to make sure your Toyota Tundra has only between 1/4 and 3/4 of fuel in the gas tank. Some of the monitors (particularly the EVAP monitor) will not run while your truck has any amount of fuel other than 1/4 to 3/4 tank.

Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on.
Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle.
Hold at a steady speed of 55 mph for three minutes.
Decelerate (coast down) to 20 mph without braking.
Accelerate back to 55 to 60 mph at ¾ throttle.
Hold at a steady speed of 55 to 60 mph for five minutes.
Decelerate (coast down) to a stop without braking.
If all other emissions systems are functioning properly, completing the drive cycle above should set the emission monitors required to pass the smog test. We recommend performing the drive cycle 2 or 3 times before the smog inspection. Using a scan tool check which monitors have become ready after each drive cycle.
 
Originally Posted by PandaBear
I remember the rule of smog is you can have 1 of the 8 monitors in not ready state.

Originally Posted by PandaBear
I remember the rule of smog is you can have 1 of the 8 monitors in not ready state.

Wow! I will run it around some this weekend and giver 'er a shot Monday....
 
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