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Smog failed due to "catalyst not ready"

Tiny
STEVE W.
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Correct. The system runs the test for the converters only at speeds between 40 and 70 mph. Slower or faster and it will not run the test because the exhaust flow is outside the "normal" speed zone the vehicle operates in. IE not enough flow at 40 and excessive flow at 70. So Toyota specifies the speed and time required and suggests staying more toward the center of the speed and a bit over the time to enable the test to run.
The idea is that gives the converter enough time to operate for the system test to say Yes it's ok or No it isn't. Toyota isn't the only one with odd rules for monitor tests, but it's one of the top 5.
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Tuesday, September 15th, 2020 AT 3:09 PM
Tiny
JIANWENT
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Got it! Sure I can drive around 60 on highway for 15-20 minutes, then once I exit from the highway, I can only drive around 30-35 before going to the smog check station, is it okay?
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Tuesday, September 15th, 2020 AT 3:27 PM
Tiny
STEVE W.
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That should be fine. Start it and let it run a bit before you start out, that will give it a chance to warm up. Sorry if it sounds like it's a bother, but Toyota for some reason made this a bad test to run. Other cars will run in like 5 minutes with random driving. Not Toyota.
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Tuesday, September 15th, 2020 AT 5:13 PM
Tiny
JIANWENT
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How many days shall I do the following cycle? For example, in the morning, before I go to work, I start the car and let it run for a few minutes, then I will drive 2-3 minutes with 25-30 MPH on the local way before going on the highway. I can drive around 50-60 MPH for 10-15 minutes, then exit the highway, drive 2-3 minutes local way arriving the company. In the afternoon I will do the similar above pattern. I usually go to work 3-4 days every week currently. Is it possible that I will miss the points when the CAT is ready, then after certain points, the CAT become not ready again?
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Wednesday, September 16th, 2020 AT 3:19 PM
Tiny
STEVE W.
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I would say that 2 days or 4 trips should make the monitor set if it is going to. You don't need to worry about missing it, once set it will stay that way until it fails the test at a later time or something resets the ECU. In theory it should run on the first trip, but It can take more.
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Wednesday, September 16th, 2020 AT 7:47 PM
Tiny
JIANWENT
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Does it necessary to be consecutive 2 days? Is 50-60 MPH on highway for 10-15 minutes okay?
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Wednesday, September 16th, 2020 AT 9:52 PM
Tiny
STEVE W.
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Nope, you just want to do it more than once. 55-60 for 15 minutes would be a minimum to be sure the test requirements are met. Longer is better in this case.
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Wednesday, September 16th, 2020 AT 10:34 PM

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