Mcon

iTrader: (1)

Hello everyone,

Let me start with this. I know is a thousands of thread related to this code, P0420 here, but this is what happened to me yesterday and I not found nothing like that.

But here we go...
I was cruising my car, I see from a little distance the red light. I pull my foot on the accelerator to go stopping, but the light changes and I hasten to follow. The car begins to lose speed, I sped to the bottom and no reaction from the car. I look my cluster to see is something wron with the car and all look okay. I stop to see what happens with it. I open the hood and look around the engine and shocked to see the catalytic 1, 2 and 3 after the first O2 sensor was red, red as when the turbo go to maximum temperature and the pipe it gets very intense red. I went and shut the engine off, wait a few minutes and returned to start the engine. The temperature was normal and nothing looked strange on the car. I try to move the car and the car only was moving at 5 miles per hour. Take the car as I could to the shop of my friend who is a mechanic and leave it there. But driving the car to the shop, the check engine light turned ON, the VSC and VSC OFF light also turn ON. I had my OBD2 machine with me, plug in and gave me the code that was P0420. 8 months ago my muffler shop guy told me that my catalytic looked and song as new. All 4 O2 sensor only have like 2 years installed and I bought Denso brand. So, my question is; Why this happened in my car without any previous warning. Someone experienced it this same situation that I had yesterday? Any help and suggestion is more than appreciated.

Mr Jokster

iTrader: (8)

Too much unburned fuel passing through the exhaust is being burned in the converter. Being that the cat got red hot, it may very well melted. Now its all clogged inside and the car cant breath thus the reason the car is running slow now. Most likely need a new cat, hopefully not all of them. but this wont fix the problem, need to find out why so much fuel is passing through (if this truly is the caused). Check your spark plugs and spark plug wires, thats usually what would cause enough fuel to go unburned. All this can happen quickly.

Mcon

iTrader: (1)

Mr Jokster,

First, Thanks for your answer.

Second, The Spark Plugs, Spark Wires are OEM and install them six months ago. The Coil are OEM as well, but those are longer, have as nearly two years.

Third, Today I when turn the car in the shop of my mechanic, he and his assistant heard that the catalyst was block when I turn the engine. My mechanic told me; I have an idea, take the O2 oxygen sensor bank 1 position 1 out and when you have it out, turn the engine again. I did it and when he heard the motor on, he said, runs the car to see how it responds. I did it and the car responded very well, with no matter what the sensor not was set on his position and plug in. I take the chance and drove my car to my house today with the sensor removed, so that way I can buy the new manifold, Up and Down gaskets, Manifold Nuts and All 4 sensors. Yes I want to buy all 4 sensor and all be new on the exhaust system and that way I don't have to thinking for years in that again. The last new MAF part was install 2 week ago and I bought it OEM as well.

Thanks again for you help bro.

PS. I really want to check why is past to much gas to the cat.

Mr Jokster

iTrader: (8)

Could just be the o2 sensor taking bad readings causing the car to run rich. I didnt mention that cause I would think a rich code like p0172 or p0175 would pop up before this happened. If its running fine, thats a good sign that the cats may be fine. I'm no expert, but I say changing the sensor may be all you need. Change it, but keep monitoring in the case it happens again.

Mcon

iTrader: (1)

I'll.... I keep monitoring my car for sure.
Thanks again.

Mcon

iTrader: (1)

Update...

This morning I remembered I had an original O2 sensor that will remove the car when I changing for a new all 4 sensors. I put it and turned on the engine. The engine began to sound normal. I dared to drive the car and then I heard he had a sound like he was strangled and then started to not respond at all. He was drowning symptoms and sounded bad. I returned to the house and I definitely indicated me that the catalytic is clogged. The most that puts me to think it is, why this happened with the cat?? Because I keep the car with all maintenance on time?? Sigh ... Such is life.