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2000 Toyota Tacoma Question: O2 sensors or catalytic converter?

 

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gibs5831, 3.4L V6, Cumming, GA, August 30, 2009, 16:30
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My 2000 Tacoma failed the emissions test - Engne light had been coming on but mechanic reset it. One mechanic said replace converter; other said it was a sensor. One has been replaced and the light came back on. Now they want to replace the other - Which costs almost the same as the cat. Is it likely that if both sensors are bad, the catalytic converter is too? Truck originally came from California.

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    dandd August 30, 2009, 17:11
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    I think that you need much better mechanic(s). If the first one "re-set" the light that is nonsense. If you have a code, clearing it does absolutely nothing. That is why in Ca the Sate will come down on you for doing this. If you have a code, there is a problem, no ifs ands or buts about it. It also sounds like the mechanics don't understand the codes, because they have replaced the wrong Oxygen Sensor. What is the Code or Codes? I do Smog Diagnosis in Calif and I find that many out of State techs are puzzled by Computer and emissions Diagnosis.

    The Code P0420 is definitely a Catalytic Converter fault and the only way to fix it is to replace the CAT. Many techs who are not really familiar with Emissions Diagnosis get fooled and think it is an Oxygen Sensor code, but that is totally incorrect. Unfortunately, if it is a California vehicle, it will need a Calif Cat or the light will come back on. The Computer has different software and needs to see a different Cat. On some Toyotas, when the new Cat is put in, they reprogram the computer for the new CAT, however, a 49 state CAT takes much of the same type of repair. The main reason the Cat fails is the the previous owner did not keep the truck well maintained. I deal with this everyday because I do Emissions work in CA. That is why if you buy a vehicle in CA, the vehicle must pass Smog and not set any lights for 90 days, or the previous owner has to pay for all repairs. Good Luck!

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    gibs5831, August 30, 2009, 19:04
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    Dandd - Thanks for the reply. I'm not sure about the code-It's my sons truck (but my $$). They put in a sensor, told him do drive about 50 miles for the thing to reset. Light came back on, so they tried putting in the one they took out back and replacing the untouched one with the new one. Lite back on. Now they say they must both be bad.

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    gibs5831, August 31, 2009, 13:57
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    Dandd - If you're still out there...The code is p420. A third mechanic has said that he has to take it to Toyota, because they are the only ones who can get a main catalytic converter for a CA truck ($1,099 just for the part). I wish I had scrapped this thing in the cash for clunkers program. The repair is going to be almost as much as it's worth.

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    Visitor, June 13, 2010, 06:59

    you shouldn't have to pay for anything those "mechanics" have done to the truck thus far because they did not fix the problem. The third guy sounds like he knows whats going on.

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    bar45, October 16, 2010, 13:48
     Rookie

    The check engine light of my 1996 Mazda 626 has been on continuously for about two weeks. Two independent mechanics here in Illinois, where I now live, did the computer analysis and determined I needed a new catalytic converter. Car has 84K miles on it.

    The car is originally from California. I just read your answer to a related question from August 2009, in which I think you say I need to replace the catalytic converter with a "California cat" or the light will come back on. Would you please explain how I should take care of this? I will be in California soon. Should I pick up a catalytic converter while I'm there, or what? Thanks!

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    Visitor, October 17, 2010, 07:38

    A P0420 is a classic CAT converter code, it is NOT an Oxygen sensor code, many shops do not get this right. Unless you do Emissions analysis on an everyday basis, which I do, many shops will miss this code. Your truck needs a new CAT and the only one to use is a factory unit, and it may need a software update as well, which is not expensive, but you need a really good computer to do the update.

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    Visitor, November 16, 2010, 21:03

    I'm having my '04 Tacaoma, 2.7L, california cat replaced right now by an exhaust shop in Shillington, PA after I got the PO420 code. . Only $500 for the double cat. Don't forget, if your vehicle is under 80k miles its covered under warrenty. Of course mine failed at 82k miles.

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    Visitor, November 17, 2010, 07:55

    You HAVE to use a Toyota CAT or the light will come back on, after market CAT Converters will not work, I have tried using them in CA and they don't have the internal components that a factory CAT does.

    dandd

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    Visitor, November 20, 2010, 07:39

    This is good information Dandd. Do you know where to get them at a good price?
    Or what kind of price should one expect to pay to replace them both.

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    Visitor, November 20, 2010, 18:13

    There is no 'deal' for Catalytic Converters that really do the job, because the Converter internals have rare meals on them like Platinum, Palladium, Rhodium and Cerium. None of these metals go on sale, unfortunately. The best CAT Converters are from the Dealership, but they are $$ NAPA Auto Parts now have California Legal Cats, but the list price is still pretty close to a factory Cat, but maybe you can get a better deal on them because I KNOW what the wholesale cost is and it is about 1/2 of the dealership price. Hope that this helps.

    dandd

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    Visitor, December 07, 2010, 22:04

    Yep cat converter. I also had a similar issue with my 97 f150 and got the runaround.Finally wrote to Attorney General and got Ford to cut me a check for brand new cat conv since my vehicle was under 80 k and less than 10yrs old. DO NOT USE AFTERMARKET ,youre taking a huge chance.

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    Visitor, December 08, 2010, 08:15

    Good job sticking up for your self. Most Cats are covered for 8 years and 80k, I don't why Ford gave you the run around in the first place, maybe a shady dealership ( not the first time ).

    dandd

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    Visitor, January 25, 2011, 15:48

    if you have a california car but are registering it sopmewhere else can you put an ordinary cat in if the computer is adjusted?

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