P0430 code cleared itself
Thread Starter
Lexus Champion
Joined: Jul 2013
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From: RightHere
P0430 code cleared itself
I was just on the brink of installing Magnaflows due to a catalytic code on my GS4 for the last three weeks. I've been smelling some catalytic sulfer here and there but not on a steady basis.
So after running some Techron through the tank and doing some highway miles the code cleared itself!
The car did get wet from the previous owner in a flood zone but it is not a flood car. The undercarraige may have seen some water briefly. No other codes at all, no O2 sensor or engine misfires.
What do you guys think? And no real performance problems other than a lopey idle and slightly sluggish of the line performance.
The exhaust place says replace the catalytics at about $900 for everything but then they have an interest in scaring me with potential problems down the road etc.
I'm thinking let's see if the light comes back on. I just came back from a highway trip about 120 miles and no CEL.
So after running some Techron through the tank and doing some highway miles the code cleared itself!
The car did get wet from the previous owner in a flood zone but it is not a flood car. The undercarraige may have seen some water briefly. No other codes at all, no O2 sensor or engine misfires.
What do you guys think? And no real performance problems other than a lopey idle and slightly sluggish of the line performance.
The exhaust place says replace the catalytics at about $900 for everything but then they have an interest in scaring me with potential problems down the road etc.
I'm thinking let's see if the light comes back on. I just came back from a highway trip about 120 miles and no CEL.
Last edited by MattyG; Sep 2, 2013 at 06:53 PM. Reason: Additional info
I have had this code throwing on and off since i got my car, it has cleared itself and reappeared several times.
from what i gather this is a very common code for the GS4, it either means an exhaust leak, bad cat, or bad o2 sensor.
If your exhaust doesn't smell bad then it's probably not the cat.
If you don't smell any exhaust leaks in the cabin or bay, it's probably not an exhaust leak
i believe the most common cause is the o2 sensor and people have had best results with the OEM denso ones.
disclaimer, all my info is from searching this forum, i have not fixed my code yet.
from what i gather this is a very common code for the GS4, it either means an exhaust leak, bad cat, or bad o2 sensor.
If your exhaust doesn't smell bad then it's probably not the cat.
If you don't smell any exhaust leaks in the cabin or bay, it's probably not an exhaust leak
i believe the most common cause is the o2 sensor and people have had best results with the OEM denso ones.
disclaimer, all my info is from searching this forum, i have not fixed my code yet.
Thread Starter
Lexus Champion
Joined: Jul 2013
Posts: 2,300
Likes: 4
From: RightHere
Thanks Ava92. The CEL came back on today but I don't smell the catalyst. It's headed over to Toyota tomorrow to see what their techs will find. If it turns out to be an O2 that would be great but I need more advanced diagnostics to be sure.
If it's the catalytic, I'll probably go the Magnaflow route which seems to work for most people.
If it's the catalytic, I'll probably go the Magnaflow route which seems to work for most people.
Thanks Ava92. The CEL came back on today but I don't smell the catalyst. It's headed over to Toyota tomorrow to see what their techs will find. If it turns out to be an O2 that would be great but I need more advanced diagnostics to be sure.
If it's the catalytic, I'll probably go the Magnaflow route which seems to work for most people.
If it's the catalytic, I'll probably go the Magnaflow route which seems to work for most people.
1. Exhaust leak Precat or at cat ( They Tear at the welds that hold the heat shields)
2. Bad Cat, clogged, they are Sturdy from factory so i would remove to Confirm.
3. Bad o2.. I doubt it.. A bad o2 would signal a bad o2 warning..
4. $40 fix which i can not disclose unless u email me (Ladislao75@optonline.net)
Good luck..
You might check your rubber vacuum hose around the top of the engine. They get vulcanized and hard as a rock. Then they crack and the vacuum is reduced, triggering the CEL. I replaced all of them in a hour or so.
Driver
Joined: Nov 2008
Posts: 91
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From: OH
My $0.02:
If you replace vacuum hose and are not in hurry or destitute, I try and use some 6mm Si vacuum hose that I get from local European garage. Cool blue color and its one thing you never need worry about again. YMMV.
If you replace vacuum hose and are not in hurry or destitute, I try and use some 6mm Si vacuum hose that I get from local European garage. Cool blue color and its one thing you never need worry about again. YMMV.
Thread Starter
Lexus Champion
Joined: Jul 2013
Posts: 2,300
Likes: 4
From: RightHere
Hmm ok there's some good advice from you guys. The car actually has been exhibiting symptoms of a catalytic and last I looked under the hood there wasn't any cracked or bad rubber under there.
The local Toyota store is actually not bad. I only got charged a half hour of labor to make sure there were no exhaust leaks and to run the Techstream on it to make sure no other issues.
They've confirmed that it's the right side catalytic - didn't try to talk me into anything really. Surprise on me. I already had gone to an independent performance exhaust place before that too. I'll update everyone after tomorrow, because it's getting the Magnaflows tomorrow a.m.
The local Toyota store is actually not bad. I only got charged a half hour of labor to make sure there were no exhaust leaks and to run the Techstream on it to make sure no other issues.
They've confirmed that it's the right side catalytic - didn't try to talk me into anything really. Surprise on me. I already had gone to an independent performance exhaust place before that too. I'll update everyone after tomorrow, because it's getting the Magnaflows tomorrow a.m.
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Thread Starter
Lexus Champion
Joined: Jul 2013
Posts: 2,300
Likes: 4
From: RightHere
So the car now has two Magnaflows. The shop used the universal fit so it was a custom fabrication for the flanges to make them fit properly. I made sure to tell them to make sure they put on the California compliant ones on it. That should keep the computer happy, and keep it ULEV.
Right off I noticed that there is a little bit more power and it's idling way better. Previously I sensed that it was laboring at idle and "chugging". It still idles at about 450-500 but it's not "cycling", just a smooth idle and quick jump off idle to 2000 rpm if I need it.
Next step is clean the MAF with some CRC just for preventative maintenance and I'll check plugs too.
Right off I noticed that there is a little bit more power and it's idling way better. Previously I sensed that it was laboring at idle and "chugging". It still idles at about 450-500 but it's not "cycling", just a smooth idle and quick jump off idle to 2000 rpm if I need it.
Next step is clean the MAF with some CRC just for preventative maintenance and I'll check plugs too.
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