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austin.c
08-06-2012, 09:42 PM
Is there any way to reset a permanent CEL Code?
I can reset the codes w/ a hand held scanner, but the permanent code refuses to erase.
When I have one P0420 code (permanent) No CEL, but when I do get my CEL, I have 2 other P0420 codes at the same time...

UtahSleeper
08-06-2012, 10:08 PM
Are you trying to clear it temporarily? From the code, it looks like your second o2 sensor thinks your cat is gone or gutted. Had this on a protege till I used a anti spark plug fouler on the 2nd sensor to move it out of the stream.

austin.c
08-07-2012, 01:41 AM
i want to permanently clear the code. The 2nd o2 sensor is spaced out w/ a non fowler, and the cat is gutted.

UtahSleeper
08-07-2012, 05:07 PM
It should clear on its own normally. Did you make your own fowler? How big of an opening did you make at the end in the exhaust stream? Does your scanner show the voltages of the 2 o2's?

austin.c
08-07-2012, 05:11 PM
I can look up anything on the scanner live if needed. I had to drill the fowler, and it is slightly larger than the o2. It refuses to clear correctly. Let me know what info you need and I can get it tonight.

UtahSleeper
08-07-2012, 05:40 PM
Wait..............do you have 1 or 2 fowlers on the o2 sensor? Should be 2. 1st is opened quite a bit to fit the o2, second goes over that and is only slightly opened up.

austin.c
08-07-2012, 06:45 PM
Wait..............do you have 1 or 2 fowlers on the o2 sensor? Should be 2. 1st is opened quite a bit to fit the o2, second goes over that and is only slightly opened up.

I have both non fowlers. exactly as u describe too.

UtahSleeper
08-07-2012, 08:25 PM
K. Definately wierd then. My protege turned off the CEL within 10 miles after doing that. Curious what your voltages will come out as.

celica9303
08-08-2012, 03:36 AM
Remove cluster, take out bulb for cel....fixed lol j/k.

Why not just put a nother sensor in? Really no benefit from not having it.

UtahSleeper
08-08-2012, 04:05 AM
His sensor works though, from the sounds of it. The problem is that since his cat is gutted, the second o2 sensor is throwing a CEL cause it see's that the cat is doing nothing. He is just simply trying to make the o2 think everything is ok.

I have seen topics elsewhere about putting resistors inline to lower the return voltage. I could just never get it to work right.

celica9303
08-08-2012, 04:19 AM
Ahhh i understand now. All my car are obd 1 so i dont gotta worry about 2 o2 sensors, no catalytic converter on either Toyota.

I've also heard of the resisotor trick. Let me know if you need and help Austin.

austin.c
08-08-2012, 01:23 PM
Got some info from the code reader last night... (and screenshots)
CEL came on while i was going to get the reader (made this simple)

Code 1/3 P0420
Catalyst System Efficiency Below Threshold Bank 1
Code 2/3 P0420
Catalyst System Efficiency Below Threshold Bank 1 (Pending)
Code 3/3 P0420
Catalyst System Efficiency Below Threshold Bank 1 (PERMANENT)

CAT TEMP11 394F
CAT TEMP12 166F
O2S12 0.000V
O2S11 3.272V

O2 Sensor B1S1
Max 19.898V 3.590mA
Meas 0.677V 2.629mA
Min 0.119V 1.016mA

O2 Sensor B1S2
Max 0.214V 1.190V
Meas 0.136V 0.761V
Min 0.000V 0.585V

MO2 Sen B1S2 (might be HO2)
Max 30.828ohm
Meas 20.490ohm
Min 0.000ohm

UtahSleeper
08-08-2012, 04:16 PM
The number seems well below what the 1st sensor is. May have to do what I did to my Altima to clear the code. Disconnect the battery for 16 to 24 hours while going out every now and then and press the brakes, turn on headlights, etc. I had a trans code that wouldnt clear and that was the only way I could clear it. Just an idea. Although its wierd that it has the code is listed 3 times.

austin.c
08-08-2012, 04:48 PM
the B1S2 has 2 separate voltage pages, one has the voltage low, the other shows a voltage almost equal to B1S1...
I will try to leave the battery off for a long while. Best I can do is 13hrs tonight.
If that doesnt work, I may try the resistor mod...

UtahSleeper
08-08-2012, 10:14 PM
Good luck. Hope it works.

Luni
08-08-2012, 10:19 PM
Im surprised Jeremy (alltracman78) hasnt popped in here yet.

Hipster Lawrence
08-08-2012, 10:36 PM
The permenent code is there because it's failed the cat monitor so many times. Obvously you need a cat and the no foulers aren't doing the trick. They don't always work.

Just put a cat on it and clear the codes. Once it passes its catylist monitor that code should disappear from the ecu's memory.

austin.c
08-08-2012, 10:48 PM
Ya, i just dont have the money right now to replace the cat. when i do, im going to have a bolt in test pipe made at the same time...

UtahSleeper
08-09-2012, 02:34 AM
The permenent code is there because it's failed the cat monitor so many times. Obvously you need a cat and the no foulers aren't doing the trick. They don't always work.

Just put a cat on it and clear the codes. Once it passes its catylist monitor that code should disappear from the ecu's memory.

Wouldnt you think that with the simple logic of the ECU's, the foulers would always work? The second o2 being pulled out of the stream and have less of an opening to measure should almost always give less of a signal. I hope this works for you just cause those damn cats are expensive, assuming this is one that is attached to the exhaust manifold.

celica9303
08-09-2012, 03:03 AM
Just get a high flow cat.....

Hipster Lawrence
08-09-2012, 12:12 PM
Wouldnt you think that with the simple logic of the ECU's, the foulers would always work? The second o2 being pulled out of the stream and have less of an opening to measure should almost always give less of a signal. I hope this works for you just cause those damn cats are expensive, assuming this is one that is attached to the exhaust manifold.

No I wouldn't. And newer ecus logic is far from simple. Some ecus try to get a response from the downstream o2 an use them for fine tuning of fuel trim. I had a mustang that was acting all kinds of crazy because the 2 downstream sensor connectors were swapped.

Hipster Lawrence
08-09-2012, 12:13 PM
Just get a high flow cat.....

On an obd2 car? That doesnt always work either.

austin.c
08-09-2012, 01:06 PM
Just get a high flow cat.....

That kinda defeats the purpose of being straight piped now, doesnt it? And NY has a yearly emissions check, but its a simple plug in the obd2 to check for MIL/CEL codes about the cat.
Looks like bolt in cat and test pipe will be the route i take next.

UtahSleeper
08-09-2012, 03:56 PM
What car do you have? So did battery disconnect over night not work?

austin.c
08-09-2012, 05:16 PM
Driving the car today, 45miles, no light, but usually takes about 100.
its a 2010 Scion xB RS7.0. Has the 2AZ-FE, but im thinking I may have the head converted to a -GE and make that 2.4l scream like my 2zz

UtahSleeper
08-09-2012, 06:07 PM
Well, guess we have to wait and see. I know older ECU's are simpler. Who knows about the new.

celica9303
08-10-2012, 02:52 AM
That kinda defeats the purpose of being straight piped now, doesnt it? And NY has a yearly emissions check, but its a simple plug in the obd2 to check for MIL/CEL codes about the cat.
Looks like bolt in cat and test pipe will be the route i take next.

Meh. High flow cats are basically a resonator( you can see rigt through em) and what little bit of baffling inside wont hinder flow at all. Remember you still need some sort of back pressure.

Hipster Lawrence
08-10-2012, 12:32 PM
That kinda defeats the purpose of being straight piped now, doesnt it? And NY has a yearly emissions check, but its a simple plug in the obd2 to check for MIL/CEL codes about the cat.
Looks like bolt in cat and test pipe will be the route i take next.

It's a fucking Xb with a Camry engine just run a cat. I gurantee you there is no more than a .5 hp gain without one.

austin.c
08-10-2012, 12:54 PM
It's a fucking Xb with a Camry engine just run a cat. I gurantee you there is no more than a .5 hp gain without one.

Im not looking for gain, im looking for sound. and a cat cat make a huge difference on the sound. MazdaSpeed 3 straight pipe w/ a cat at idle you cant even hear it on. when the cat is removed, its loud as hell.