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Toyota Repair/toyota sienna catalytic converters


QUESTION: About 3 months ago, the check engine light came on and after diagnostics, the O2 sensors were replaced. We understood at the time that it might end up being the cat converters. The light just came back on and now the shop (not a dealer) is telling me that all 3 converters need to be replaced to the tune of $2500 for parts and labor. The van is a 2002 with about 175k miles. Is it common for all 3 converters to need replacing? If we do this, can we expect to still drive the van for another 50-75k miles? I don't want to get a new car but don't want to sink money into a car with a short life span. Your input is greatly appreciated!

What I would recommend is to get another opinion pfererable from a Toyota dealer, by the way do you have the diagnostic code numbers available? I doubt that all three converters go bad, it sounds like the repair shop just wants to replace all just to cover themselves. The two front converters do go bad, this is not uncommon but is usually either bank one or bank two so if you can reply with the specific code numbers I can look into this a little deeper

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QUESTION: Thanks for the reply! Unfortunately, I was not provided with the diagnostic codes. They did explain why they said all converters need to be replaced. They said their understanding is that if the back one is bad, then all others in front of the bad one need to be replaced too. I did consult with the local Toyota dealership and they seemed to believe it could just be a single replacement. I will take it in to them to verify the diagnosis.

That's a good idea, spending about $90 to have the tests and dianostics done may save you a lot of money, the reasoning of that repair shop doesn't seem right,neither does their unwillingness to offer an explanation, there is a way to test each converter using the diagnostic equipment the dealer has and they should offer you a printout of converter performance and explain why they would need to be replaced  

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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