Smog Check failed for Catalyst 'Not Ready'

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The drive cycle that The Nuke posted is a good generic drive cycle, but it would be better to locate, download, and print out a readiness drive cycle specific to your 2004 Highlander and follow it TO THE LETTER. Many drive cycles have some minor differences that, if missed, will cause it not to "ready" the computer. Before you start, there needs to be a specific amount of gas in the tank, usually between 1/2 and 3/4 tank. The "secret" to getting a drive cycle to run and make everything "Ready" is that the engine's temperature needs to be between specific temperatures for a specific number of hours (typically between 40 to 95 degrees for 8 hours), or it will not run. The high ambient temperatures that we have been experiencing in many parts of the country (especially in CA) can cause it to NEVER become ready.
 
Originally Posted By: mk378
Unplug a sensor to make it throw a code deliberately. Then plug the sensor back in and make sure that stored code is remembered when you start and stop several times. If the ECU is not getting backup power, it will go to no codes not ready every time you turn the key off.


This morning, I unplugged the front O2 sensor, and it threw a P0031, as it should. I did not erase the code, so I will check later today if it is still there. I will also leave it until tomorrow morning overnight to see what happens.

Thanks for the suggestions!
 
The O2 sensor is plugged back in, right? But you should always have a cheaper reader which can give you I/M readiness monitors and Mode $6 data given how cheap those things are these days.
 
Originally Posted By: eljefino
Has it been hot? Over 95'F or so and the things might not run.

Toyota (camry) with that motor got a firmware update for the cat, to make the monitor less sensitive.

A spark plug anti-fouler on the rear o2 might just help things along if it's on the borderline and can't make up its mind.


Yes, it has been unseasonably hot... It is starting to be mid 90s during the day and cools off in the high 60s-70s at night. Once I finish the current test to see if the ECU is getting backup power, I will reset it and hopefully we can move this thing along.
 
Originally Posted By: Vikas
The O2 sensor is plugged back in, right? But you should always have a cheaper reader which can give you I/M readiness monitors and Mode $6 data given how cheap those things are these days.


Yes, I plugged it back in, before I even left home. I did notice however before I shut the car off, I scrolled though the gauges, that the engine was still in open loop (5 mi drive) so not sure what to make of that. Could be that the code is causing that, or the ECM did not see the sensor - we'll see.
 
Originally Posted By: wag123
The drive cycle that The Nuke posted is a good generic drive cycle, but it would be better to locate, download, and print out a readiness drive cycle specific to your 2004 Highlander and follow it TO THE LETTER. Many drive cycles have some minor differences that, if missed, will cause it not to "ready" the computer. Before you start, there needs to be a specific amount of gas in the tank, usually between 1/2 and 3/4 tank. The "secret" to getting a drive cycle to run and make everything "Ready" is that the engine's temperature needs to be between specific temperatures for a specific number of hours (typically between 40 to 95 degrees for 8 hours), or it will not run. The high ambient temperatures that we have been experiencing in many parts of the country (especially in CA) can cause it to NEVER become ready.


Do you know what happens if I cannot pass a smog check because of the CAT not being ready? Being in CA, is there a way to get a waiver and do a tailpipe test? Not sure what happens next if I can't get the IM Monitors to complete. I've already paid the REG fees to avoid penalty fees, but without a smog test cert, CA will not issue me my new registration for the year.
 
Originally Posted By: MysticGold04
Originally Posted By: Vikas
The O2 sensor is plugged back in, right? But you should always have a cheaper reader which can give you I/M readiness monitors and Mode $6 data given how cheap those things are these days.


Yes, I plugged it back in, before I even left home. I did notice however before I shut the car off, I scrolled though the gauges, that the engine was still in open loop (5 mi drive) so not sure what to make of that. Could be that the code is causing that, or the ECM did not see the sensor - we'll see.


It will stay in Open Loop mode as long as the CEL is illuminated. A DTC can exist in the system, but it will not prevent Closed Loop operation if it is not active (CEL illuminated).
 
The monitor that gives you the most grief on a Toyota is the EVAP monitor(and partly why the 2nd gen Prius was introduced with a new EVAP module including a leak-down pump that made its way into other Toyotas). The CAT and HO2S monitors are constantly running but there is a drive cycle described in TIS to get those to run.

It's best to pay your registration fees first and then smog your car, in CA a cop might nail you for expired tags but the DMV will flag it as paid but not complete. BAR switched over to an OBD-II scan-only inspection for 2001-newer cars.
 
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Originally Posted By: nthach
The monitor that gives you the most grief on a Toyota is the EVAP monitor(and partly why the 2nd gen Prius was introduced with a new EVAP module including a leak-down pump that made its way into other Toyotas). The CAT and HO2S monitors are constantly running but there is a drive cycle described in TIS to get those to run.

It's best to pay your registration fees first and then smog your car, in CA a cop might nail you for expired tags but the DMV will flag it as paid but not complete. BAR switched over to an OBD-II scan-only inspection for 2001-newer cars.


Interestingly enough, when I took it for the test, the CAT monitor was the only one that had not run. I have already paid the REG fees, so hopefully here in the next couple of weeks, the monitors will have set and I can take it back in. I'm still not really sure on what should be done with it first. I suppose the Thermostat and ECTS is cheap enough to have done... especially since I plan on keeping this car until it won't drive anymore. I have not had a single major problem with this car, only routine maintenance. I did have the water pump changed at about 140k miles because it started dripping.
 
Originally Posted By: SHOZ
Did you ever look at the O2 voltages while driving?


No, Sure haven't. I replaced both at the same time with Denso OEM about 3-4 years ago...

I'm assuming this requires a special tool to accomplish?
 
I had a 2002 Camry with a 2AZ-FE. Burned 1 qt of oil every 2k-2500 miles. So I figured the P0430 was plugged catalyst. I put a nonfouler on the rear O2 sensor and went another 100k. So IMO the catalyst efficiency programming threshold is too sensitive. I researched it once, its something like below 90% good it goes off. Which explains why I never had any issues after the nonfouler install. No Cel, no back pressure on the highways, etc. Never changed it. broken valve at 354k ended the relationship with that car.
 
Originally Posted By: MysticGold04
Originally Posted By: SHOZ
Did you ever look at the O2 voltages while driving?


No, Sure haven't. I replaced both at the same time with Denso OEM about 3-4 years ago...

I'm assuming this requires a special tool to accomplish?
Just a generic OBDII scanner.
 
Originally Posted By: MysticGold04
Originally Posted By: wag123
The drive cycle that The Nuke posted is a good generic drive cycle, but it would be better to locate, download, and print out a readiness drive cycle specific to your 2004 Highlander and follow it TO THE LETTER. Many drive cycles have some minor differences that, if missed, will cause it not to "ready" the computer. Before you start, there needs to be a specific amount of gas in the tank, usually between 1/2 and 3/4 tank. The "secret" to getting a drive cycle to run and make everything "Ready" is that the engine's temperature needs to be between specific temperatures for a specific number of hours (typically between 40 to 95 degrees for 8 hours), or it will not run. The high ambient temperatures that we have been experiencing in many parts of the country (especially in CA) can cause it to NEVER become ready.


Do you know what happens if I cannot pass a smog check because of the CAT not being ready? Being in CA, is there a way to get a waiver and do a tailpipe test? Not sure what happens next if I can't get the IM Monitors to complete. I've already paid the REG fees to avoid penalty fees, but without a smog test cert, CA will not issue me my new registration for the year.

Yes, I do know what happens, we have the same smog checks here in Texas where I live, and the vehicle can NOT be registered without passing. I know that it is extremely frustrating, I have gone through this sort of thing myself, that is how I found out about the temperature requirement. What I ended up having to do in one case was to have the car stored overnight in an air conditioned building for 14 hours with a battery charger on it. I scouted out a route in advance with another car and practiced the drive cycle so I could be reasonably sure that I could do it accurately, then I ran a drive cycle by-the-book and all of the IM monitors went to ready. FYI, on this particular car it was the CAT monitor that stubbornly wouldn't turn ready, just like yours.
I forgot to mention, the battery condition and state of charge (as well as a weak charging system) can also keep the IM monitors from becoming ready because of out-of-range voltages.
 
Originally Posted By: Vikas
I thought all states allowed one incomplete I/M for 2001+ cars

To pass an emission inspection ONLY the evaporative monitor can be incomplete (not ready).
 
It is used to be little bit convoluted in the past. If it was re-inspection, then you could not have CAT incomplete but otherwise one incomplete used to be allowed including CAT. I had used that loophole couple of times. Heck, I had to time it perfectly before transitioning from incomplete to CEL :)
 
Originally Posted By: wag123
Originally Posted By: Vikas
I thought all states allowed one incomplete I/M for 2001+ cars

To pass an emission inspection ONLY the evaporative monitor can be incomplete (not ready).

Some states will give certain cars a pass if another monitor isn't complete or fails - I know CARB/CA BAR does give older Nissans a pass during the OBD-II phase of a smog check since one of the monitors(misfire or knock sensor) is buggy. The I/M database is kept fairly current.
 
Originally Posted By: Vikas
It is used to be little bit convoluted in the past. If it was re-inspection, then you could not have CAT incomplete but otherwise one incomplete used to be allowed including CAT. I had used that loophole couple of times. Heck, I had to time it perfectly before transitioning from incomplete to CEL :)

NOT where I live! As it stands right now where I live we are only allowed one "Not Ready", and it can ONLY be an EVAP "Not Ready". They don't give anybody a break here, they use a completely computerized system and it either passes or fails you, NO grey area. If after three repair attempts have been made by a licensed repair facility it still won't pass a retest, a special waiver can be applied-for and possibly granted after the vehicle undergoes an inspection and approval by a DPS agent, but this is difficult to obtain unless you are a low income individual or drive less than 5k miles per year, and it has to be done again every year (they make this process purposely difficult). Furthermore, they will flunk you if the CEL is lit even when all monitors are "Ready". Some vehicles will light the CEL for other things, like a transmission problem.
 
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