How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Ron Z. Your Own Question

Ron Z.
Ron Z., - Toyota Tech -
Category: Toyota
Satisfied Customers: 14208
Experience:  18+yrs experience. State Inspector and Toyota Diagnostics
18617752
Type Your Toyota Question Here...
Ron Z. is online now
A new question is answered every 9 seconds

Toyota Sienna: I have a 2003 Toyota Sienna that failed emissions

Resolved Question:

I have a 2003 Toyota Sienna that failed emissions inspection with code P0420 (catalyst system efficiency below threshold bank 1). The catalytic converter, alternator, manifold and O2 sensors have been replaced but it again failed inspection today. What should I do now?
Submitted: 10 months ago.
Category: Toyota
Expert:  Ron Z. replied 10 months ago.
Hello! Welcome to the site! Thanks for coming! I'm Ron Z. I'm here to provide as much information and insight as I can, to best answer your question.

I'm sorry the Tech you requested was not available to assist you today. It appears Skyvisions (great Tech by the way!) is currently "Offline". Hopefully I can be of some help in his place...

Just a few questions...

When you say the "catalytic converter was replaced" - can you tell me which one was replaced? It's location? And when you replaced this, what brand name converter was it replaced with?

When you say the "manifold" was replaced- was this an exhaust or intake manifold? And if it was an exhaust manifold, can you tell me which one was replaced?

Thanks!


Customer: replied 10 months ago.


UPSTREAM CATALYTIC CONVERTER had rusted thru and was replaced with a new one. Both intake and exhaust manifold were replaced with certified used ones.

Expert:  Ron Z. replied 10 months ago.
Ok. What I'm trying to get at here is, on this vehicle, the P0420 is a very common and straight forward code pointing to a fault with the Warm-Up Converter for Bank1. This converter is located on the side of the engine closest to the windshield and and is built into the Exhaust Manifold. So, if you only replaced one, and it was the front one- it's the worng one. If you replaced the one closest to the widnshield, and it was "certified used" - first, this is Illegal in many States, and second... usually never solves the problem. If the converter that was repalced was the correct one, and it was a "universal" (the old one was cut off and the new one welded in place), again, this doesn't meet Toyota-specs and again, usually never solves the problem. I'm just trying to make sure you 1. Replaced the correct item 2. Replaced it with a Toyota-spec part.

Here's the location:


Here's what the correct one looks like:
Customer: replied 10 months ago.


Will take diagrams and replies to mechanic that did the work and find out for sure if he had the right parts and will contact you again after he sees this. Thanks.

Expert:  Ron Z. replied 10 months ago.
Sounds good. Again, if the exhaust manifold WITH converter (the 2nd image I sent) on the CORRECT side of the engine WAS replaced... but it was "used" - this doesn't solve the problem. AND, like I say, in MANY States... Illegal! I think you'll find if you replace the correct part with the correct version, you'll be just fine. I've seen this many many MANY times. It's a very common fail item on these vehicles.

Please remember the website WILL NOT automatically compensate me with a part of your deposit or from your subscription WITHOUT YOUR RATING! Please use the Rating System and *Rate My Service* if the information/advice I supplied has helped you. If you have any more questions, use the "Reply" tab – I'm always happy to answer follow-up questions! Follow-ups are always FREE! Even after you rate! Thank-you!


Ron Z., - Toyota Tech -
Category: Toyota
Satisfied Customers: 14208
Experience: 18+yrs experience. State Inspector and Toyota Diagnostics
Ron Z. and 7 other Toyota Specialists are ready to help you

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • THANK YOU, THANK YOU, THANK YOU!! I've got my baby back. Tomorrow I will get a tank of high octane, remove the top, go for a long long ride and enjoy my car. THANK YOU! Jughead USA
< Last | Next >
  • THANK YOU, THANK YOU, THANK YOU!! I've got my baby back. Tomorrow I will get a tank of high octane, remove the top, go for a long long ride and enjoy my car. THANK YOU! Jughead USA
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
  • Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
  • Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
  • Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Auto Technician

    Satisfied Customers:

    278
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Auto Technician

    Satisfied Customers:

    278
    16 years of experience
  • http://ww2.justanswer.com/uploads/EU/eurotec/2012-6-11_13153_mpjaphoto.64x64.JPG Marty's Avatar

    Marty

    ASE Certified Technician

    Satisfied Customers:

    167
    ASE & Bosch Master Tech. 30 years experience.
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    Toyota Technician

    Satisfied Customers:

    1132
    ASE Master Technician advanced level specialist. Wisconsin certified emissions state inspector
  • http://ww2.justanswer.com/uploads/CA/caprio23/2014-4-30_201741_20121205122939.64x64.jpg Anthony's Avatar

    Anthony

    ASE Certified Technician

    Satisfied Customers:

    373
    ASE Master Automobile Technician with over 20 years exp. in this field.
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    9
    Toyota tech. ASE Certified Technician
  • http://ww2.justanswer.com/uploads/SK/skyvisions/2012-6-9_23736_JACropped3.64x64.jpg Skyvisions's Avatar

    Skyvisions

    ASE Certified Technician

    Satisfied Customers:

    11403
    Toyota Master Diagnostic
  • http://ww2.justanswer.com/uploads/genchigenbutsu/2009-05-09_003043_cimg16431.jpg Genchi Genbutsu's Avatar

    Genchi Genbutsu

    Toyota Master Technician

    Satisfied Customers:

    3425
    Toyota Certified Master Diagnostic Technician, ASE Master Technician with L1 Advanced Engine