Emission incomplete, "Cat" blinking

[ziggyk]

About one year ago I had first MIL on my Camry 1995 1MZ.. 177k
I drove for while thinking it has OBDI. Then I found it is OBDII then purchsed the scanner.
I November last year I scaned it for firs time and, got code for oxygen sensor. I belive it was bank 2. The o2 sensor next to rock&pinion.
Replaced with "Denso". Reset the code then couple days later got P0401. Foud bad EGR modulator, replace with new original part, also cleaned EGR valve.
Reset the codes, the MIL light never came on. I tought all good.( did 1000 miles)
Last week, a month before inspection I connect the scanner: No DTC codes present and monitoring shows incomplete "cat" and "o2" blinking.
Reset again and start to drive , city and higways about 110miles. Connect scanner o2 is fine, only "cat" not comleted. I drove more with this specific pattern.
Drove highway 15min speed 50mph then local 15min 30mph, still Cat failed to complete. Also I drive with O/D off for 10 min, then A/C on for a few minutes still "cat" blinking.
So far I did 160 miles .
I read similar post by "73 sport" and "nervous" on this forum but still can not figure out what is the problem.

1) Cat replace 10k with Magna flow.(broken flex pipe)
2)Fuel filter 10K
3)Gasoline 91oct
4)new Egr modulator, Cleaned EGR valve.
5) new oxygen sensor

Anybody help please.

[73sport]

It does have a cat, its just after market? Can you post your trims and any other data?

Read this section. It took a couple of tries and the engine load, temp at startup, speed and duration all matter. . . .


P0401 related to Catalyst Monitoring Y/N?

Specifically this post #72

P0401 related to Catalyst Monitoring Y/N?

Follow it to the letter and see what comes of it. For me it was difficult to accomplish as I was backing up traffic and making a hazard. IMO - having this occur natually as part of ones commute is out of the question. As in it will never happen.

As stated; it will never pass if the MIL is on so you likely have other issues to deal with.

When is the last time the intake was off for a thorough cleaning of the EGR passages? You might start there and maybe uncover something else along the way.

[fenixus]

maybe it's time for new rear (post-cat, under car) oxygen sensor? it is the one that monitors the Cat efficiency and actually "completes" the emission test (in ECU).

your original one might be slow and making it next to impossible for ECU to complete the testing procedure.

Normally it's a piece of cake to complete the CAT monitoring test, I can do that in a few mile trip, a bit of highway and a bit of city driving.

[ziggyk]

73sport Thank you for respond.

1)After market Cat 'magna flow" 10k on it.
2) Intake never was off for cleaning. (only EGR was cleaned)
3)I have Innova scanner, and do not know yet how to transfer data to PC.( I wll try to learn how to do it) I do not know what is trims?
4) Mil light is OFF since I fixed p0401.(over 1000 miles)

As weather permits I have job to do on the valve cover which is leaking oil.That would be good time to clean intake, replace spark plugs , using Bosh 4 electrodes now 70k on it.
I will remember this pattern on 72 post.

fenixus, thank you
I think this is good idea with this after Cat oxygen sensor. I may do this first, because that will not take long and my inspection need to be done by the end of april and the job with valve cover and intake will take a while, so I will have to use scooter to get to work.. litte to cold.
With my two nissan sentra it takes 80 miles to comlete the emission.

I will keep posting as it progress .
Thank you again

[ziggyk]

I replaced the post catalic "oxygen sensor" but that did not help., still "cat" shows not completed.
Would it be possible that "catalic converter" got bad when I was driving when my oxygen sensor was bad and possibly there was mixture to reach ?
That was oxygen sensor between engine and firewall which I replaced last year Now I have both oxygen sensors new, before cat and after.


any idea?

[fenixus]

do this.

warm up the car a bit in parking lot and take it to highway, drive at 50-55mph for at least 15 minutes at a steady pace, no acceleration or deceleration unless necessary.
then after 15 minutes passed, take a closest exit to city and drive it GENTLY (the lower RPM the better, try not hitting above 2.5k RPM when moving from traffic lights) at max 35mph (do NOT exceed) for another 15 minutes.
it will get marked as complete very fast during/after that.

That's how I make it complete, works every time my 5s-fe and 1mz-fe.

[ziggyk]

Fenixus, I tried that pattern before and still did not passed.
I am calling for bad catalic converter, anybody agree?

Thank you

[73sport]

Zig,
Follow this to the Letter! My car was not forgiving and wouldn't settle for anything less than what it says here.

Including the whole start up temp! When you can do this w/out error and still doesn't work lets talk about it again. but hopefully it will work for you!

Specifically this post #72

P0401 related to Catalyst Monitoring Y/N?

[ziggyk]

73sport. I could not believe my eyes it is completed after I did your exact drive pattern.
I worm up engine , then I drove to the entrance to highway. Turned off engine, restart. Checked IAT -75degree, engine temp over 175.
I started to drive on higway at speed 52mph set cruise control on, after 3 min slow down to 42mph, then drove 7min . At exact 7min the emission kick in completed, green light came on. Wow
I am especialy happy because in two days is my inspection .

Thank you once again everybody for helpful advices.

[fenixus]

gen3 V6's computer is very picky on marking the CAT test complete
gen4 is much more forgiving in this matter.