: Both Catalysts died???



gtirsmiley
11-01-12, 08:42 AM
Hello,

I've been having this on/off recurring Check Engine Light.. I got the code scanned, and it's two codes; P0420 and P0430 which keeping coming back, no matter how many times I clear them.

The description given for the codes are: "Catalyst Sys Efficiency below Threshold (bank1)" and the other one is for bank 2.

I tried to do a cheap fix by 'gutting' both of them, but still no luck, just a nice increase in exhaust sound, but after driving for a while the CEL came on again. I didn't get the item to scan the codes, but I'm assuming its the same problem.

Now I didn't go through warranty because I'm in Dubai, and the emission warranties are different than Canada/USA. Since I have a 2006 STS, I'm not covered anymore.

So I need a solution for the CEL. I'm not sure how much an OEM catalyst costs, but I've heard horror stories of about $2000+ and I just can't afford that now. Is there a way to trick the sensors, or short them? Would general catalysts from lets say Magnaflow be sufficient enough to stop the CEL from appearing?

Thanks for any feedback.

M5eater
11-01-12, 08:48 AM
spark plug non-fouler.

Google. :shhh:

generic cats will throw a CEL if left by themselves in all likelyhood.

gtirsmiley
11-01-12, 09:07 AM
I knew I wasn't crazy. I heard about this technique before.

Found a write up in a Mitsubishi Evolution forum. http://forums.evolutionm.net/evo-how-requests-questions-tips/215795-5-o2-cheater-non-fouler-how.html

I guess I can give it a try, but not sure if I'll be able to find that part here in Dubai.. and I don't have time to order them in from the States.. :hmm:

Edit: Fair enough, but we have 2 sensors on each Cat for our cars.. would we just need non-foulers for the sensors that are closer to the rear of the car?

M5eater
11-01-12, 09:16 AM
I knew I wasn't crazy. I heard about this technique before.

Found a write up in a Mitsubishi Evolution forum. http://forums.evolutionm.net/evo-how-requests-questions-tips/215795-5-o2-cheater-non-fouler-how.html

I guess I can give it a try, but not sure if I'll be able to find that part here in Dubai.. and I don't have time to order them in from the States.. :hmm:

Edit: Fair enough, but we have 2 sensors on each Cat for our cars.. would we just need non-foulers for the sensors that are closer to the rear of the car?

the car has 4 o2 sensors, the downstream ones (ie the ones past the cats) are the ones that monitor catalyst effeciency.

The upstream sensors are the ones that adjust fuel trim to make sure the engine is running properly.

You only need to put foulers on the rear ones.

You can also solder in a resister to the singal line of either O2 sensor as an alternative. Since you're directly adjusting the signal to trick the PCM into thinking the O2 is giving a 'good' read, this is typically more effective than the fouler trick, and you should be able to find the $2 resistors in Dubai.


o2 resistor mod
google :shhh:

gtirsmiley
11-01-12, 09:34 AM
the car has 4 o2 sensors, the downstream ones (ie the ones past the cats) are the ones that monitor catalyst effeciency.

The upstream sensors are the ones that adjust fuel trim to make sure the engine is running properly.

You only need to put foulers on the rear ones.

You can also solder in a resister to the singal line of either O2 sensor as an alternative. Since you're directly adjusting the signal to trick the ECM into thinking the O2 is giving a 'good' read, this is typically more effective than the fouler trick, and you should be able to find the $2 resistors in Dubai.


o2 resistor mod
google

Hmm..let me google this mod and get back to you!

----------


the car has 4 o2 sensors, the downstream ones (ie the ones past the cats) are the ones that monitor catalyst effeciency.

The upstream sensors are the ones that adjust fuel trim to make sure the engine is running properly.

You only need to put foulers on the rear ones.

You can also solder in a resister to the singal line of either O2 sensor as an alternative. Since you're directly adjusting the signal to trick the PCM into thinking the O2 is giving a 'good' read, this is typically more effective than the fouler trick, and you should be able to find the $2 resistors in Dubai.


o2 resistor mod
google :shhh:

Alright. Googled the resistor mod, while it does seem easier (parts wise) , I'm not too keen on cutting the sensor wire and then splicing things back together. I'll have to search all over the stores on Saturday to see if I can find the non fouler..

Otherwise I might get a machine shop to make me something similar to it. I believe it needs to be 18mm and 1/2" from the inside?

M5eater
11-01-12, 07:40 PM
Sorry, I'm not familiar with the thread size.

is3_ftw
11-02-12, 12:37 AM
I have done the anti-fouler(mechanical o2 simulator) on my car. It works like a charm, as long you drill one adapter 2-3mm bigger than the sensor. I dont have cats on my car and I pass emissions. Only bad thing that could happen, is that the sensor closer to the rear might be directly pointing towards your frame. It is for my car and I had to relocate the bung further down stream.

I chose this route, because I heard of faulty connections on the electronic o2 similators


good luck with your issue

gtirsmiley
11-04-12, 12:17 PM
Thank you both for your contributions to this thread.

I went to a machine shop, and showed them pictures of some of the install guides for these non-foulers, with a bit of a language barrier, the pictures helped alot to explain what I needed done.

They made me these two bolts for around 30$ (pricey compared to the original but considering they made it for me in an hour..I think its money well spent) then I installed them and cleared the CEL's and praying the damn light stays off !


http://img120.imagevenue.com/loc24/th_043378972_IMG_20121104_164523_122_24lo.jpg (http://img120.imagevenue.com/img.php?image=043378972_IMG_20121104_164523_122_24 lo.jpg)

Will let you guys know how it goes. I had them make the bolts about 7-8cm long..hopefully its long enough!

is3_ftw
11-04-12, 01:27 PM
Good luck and hope it helps.

M5eater
11-04-12, 03:18 PM
those look pretty neat.

if it comes back just clear it again. sometimes it may take a few tries before she turns off.

gtirsmiley
11-04-12, 05:10 PM
Damn it :(

It came back after about 100kms of driving.. :banghead: This is driving me nuts!

I will take your advice and try getting it cleared again M5.. I really hope it goes away soon and forever!

M5eater
11-04-12, 06:03 PM
Damn it :(

It came back after about 100kms of driving.. :banghead: This is driving me nuts!

I will take your advice and try getting it cleared again M5.. I really hope it goes away soon and forever!

is the end that threads into the o2 bung on the car closed off partially?

That's the primary reason for using the non-foulers besides moving the O2 further away.

http://img102.imageshack.us/img102/5680/img1344mh4.jpg

see the non-fouler in the middle? That's what yours should look like.

is3_ftw
11-04-12, 08:30 PM
^^^^agreed.

Basically, what your doing is reducing the amount of exhaust to the o2 sensor. Its tricking the computer that your catalysts are still good

gtirsmiley
11-05-12, 12:02 PM
well i had the extension pulled out and looked at the hole going into the exhaust and it was considerably bigger than the one in the picture above, so i got a washer and put it into the part where the sensor would go in. the washer was a tight fit with a 4mm hole.. cleared the dtc and yet again the light came back on. also I've noticed that it seems to come back on after every 3-4 times i turn the car off and on, is this a coincidence or is it part of the ECU check?

i believe my last solution with the extension is to get it welded shut at the top and then have it drilled with a 2mm drill bit. do you guys think that would help?

gtirsmiley
11-06-12, 12:42 PM
Well this is my (2nd) last resort.. ofcourse the resistor mod would probably be next if this didnt fix it !!

Before:
http://img281.imagevenue.com/loc117/th_221627868_IMG_20121105_00290_122_117lo.jpg (http://img281.imagevenue.com/img.php?image=221627868_IMG_20121105_00290_122_117 lo.jpg)

After:
http://img179.imagevenue.com/loc158/th_221639191_IMG_20121106_00292_122_158lo.jpg (http://img179.imagevenue.com/img.php?image=221639191_IMG_20121106_00292_122_158 lo.jpg)

I didn't get the chance to clear the CEL though, so will not be sure if it worked or not just yet.

M5eater
11-06-12, 01:24 PM
That may be too small.

gtirsmiley
11-06-12, 01:57 PM
It previously had a 4mm washer in the inside of the extension.. Now I've removed the washer and closed the top with a 2mm hole.. :banghead:

I dont know what's going to happen but I hope its just big enough to let small seaps of air through to the sensor

M5eater
11-06-12, 02:22 PM
Does this car have narrow or wideband sensors?

Anyone know?

Ludacrisvp
11-06-12, 03:14 PM
Does this car have narrow or wideband sensors?

Anyone know?

When I asked hptuners about doing a tune the first thing they said was get wide-band sensors. Now that may have been the generic answer to a newbie on a forum but it could be accurate. I bet the V guys might know.

is3_ftw
11-07-12, 10:39 PM
Sounds like that you might have to fumble around with the hole. Drill 3mm each time you get a CEL. Then when the CEL doesnt come on, then you found the sweet spot.
You actually want the exhaust covering the sensor. If its not getting enough or to much exhaust, the CEL will be thrown. Are you sure there isnt a spark plug anti-fouler around?

Do you really have to get it fixed or you just annoyed at the light? If its the latter, then unplug the bulb behind the dash where the CEL is. No light ;)

dkozloski
11-09-12, 01:33 AM
If you have a CEL the remote start doesn't work.