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 carguy1 Your Own Question
carguy1, auto technician
Category: Toyota
Satisfied Customers: 28366
Experience:  25 Years experience all makes and models.Nissan factory trained,Certified Subaru Tech
Type Your Toyota Question Here...
carguy1 is online now
A new question is answered every 9 seconds

My aurion has check engine light come on with traction

Customer Question

Hi my aurion has check engine light come on with traction control what should I do ?
JA: Does the light stay on, or does it blink?
Customer: doesnt blink
JA: What is the make/model/year of your car?
Customer: 2010 Toyota aurion
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: all 6 spark plugs changed recently serviced
JA: Anything else you want the mechanic to know before I connect you?
Customer: the code says the system too lean what is that mean
Submitted: 7 months ago.
Category: Toyota
Expert:  carguy1 replied 7 months ago.

My name is ***** ***** give me a moment to review your question Thanks.The site will prompt a call.I will let you know if it's necessary

Expert:  carguy1 replied 7 months ago.

Do you happen to know the specific code or codes?

It's ok if not, but they do start with a P

let me know, thanks

Customer: replied 7 months ago.
P0174, p0171P, p0174p
Customer: replied 7 months ago.
Sorry system doesn’t allow me to enter my no
Customer: replied 7 months ago.
I am from Australia
Expert:  carguy1 replied 7 months ago.

Ok, no problem

Check it for intake manifold leaks or a problem with the mass air flow sensor. The codes essentially mean there is to much air going into the system. Since it's happening to both banks, I suspect the issue is something didn't get tightened properly after the plugs were installed or there is an issue with the mass air flow sensor. It is also possible the fuel pump is weak, but I find that to be unlikely. Mostly because this has happened after the spark plugs were done.. Make sure the air filter is tight as well.

Please let me know if there is anything else I can do to earn a 5 star rating from you.
Just Answer does not compensate me for my time and resources, you do when you rate my answer by using the stars at the top of the page. Payment for your question includes any follow-up questions you may have. Free trials and subscription questions still require ratings. Your question does not close after you rate. You will still be able to contact me by replying to this post.
Thank you so much!

Customer: replied 7 months ago.
Changed all 6 spark plugs
Customer: replied 7 months ago.
Recently serviced
Expert:  carguy1 replied 7 months ago.

I understand that, I am saying something may have left an air leak that is causing these codes to come up.

This isn't a spark plug issue, this is a lean mixture, this means it's getting to much air into the air-fuel mixture. This is what's causing the codes to come up.

The most common cause is either a leaking intake manifold or a faulty mass air flow sensor. Even something like a loose clamp on the throttle body can cause these codes to appear. Since they are together you know it's something that will affect the whole engine, not just one bank

Customer: replied 7 months ago.
Previously was only two codes p0171 and p0174, after changing spark plugs and deleting codes P0243 came on. That one gone now I don’t know how. And now those three came on again ��
Customer: replied 7 months ago.
Can someone talk to me please
Expert:  carguy1 replied 7 months ago.

Try to understand I am working with several curstomers. I will not leave you hanging on here, but I need some time to go back and forth. Originally you stated P0171 and 174, are these codes the only codes you are showing and did you replace the spark plugs to try and resolve these 2 codes?

Customer: replied 7 months ago.
Okay, I am gonna explain everything again.-2010 Toyota Aurion Prodigy Australian Version.
-I owned this car since Nov 2015 @ 137,xxx kms.
- minor serviced right away
- major serviced after @ 150,xxx k or around there, done fluids flushed and air fuel filter changed.
Car used to smell weird if I accelerated bit quickly. Mechanic didn’t have idea and said may be cabin filter. I didn’t think that was the problem but still changed it. Smelling problem didn’t go away. Car was driving okay. I keep driving.
- Next service done, air con vents cleaned for smell. Didn’t help enough.
- This time car was about to be due for service but problems occurred prior to that. Started to take longer to start(4-5 second, even twice sometimes).
-Started to consume more fuel, lack of acceleration, then check engine light came on with TCS on.
- Code read by my cheap tool P0171 and P0174
- I erased it. Didn’t come on for few days but problems were still there.
- Took to the mechanic asked for service and explained the problem as well. But they didn’t do anything except oil and filter change because there is no code they said. I asked them to change the air filter as they were suggested me in previous service. And I believe they did. Mechanic suspect the spark plugs for the problem.
- I drove home. Light back came on after 30-40 kms.
- I tried to change spark plugs myself as they quoted expensive. And found out one of the plug was just hand tight and the other one was not even hand tight ( very loose, turn few round, off the hole). Plug and coil both were burned and black. Checked the value of pins of the coil with meter, were very similar to reading with other 2-3 coils. Thought coil is still good. Changed all 6 spark plugs, the best ones ( NGK) that the local auto shop offered. And reset the code
- Check engine light came on again without TCS this time.
- My cheap tool read different code ( P0243) this time
- Opened the hood looked if I have forgotten something, didn’t see anything. Closed and deleted the code.
- Added some injection cleaner in the tank.
- Car drove little better few days
- Light came back on again after few days with TCS again �� ��
- And this time my tool is reading P0171, P0174 again and P0173P, P0171P. * P = Pending I found out.Now, could you please tell me what is could be ? What should I do next ?Regards
Expert:  carguy1 replied 7 months ago.

P0171 and P0174 codes are for lean conditions on both banks of the engine. This means the O2 sensors see to much air in the air/fuel mixture.

As stated above. This means air is entering the system someplace, or there isn't enough fuel.

This leaves a lot of options, however, since the codes are for both banks of the engine that tells me it's not a bad O2 sensor or some type of intake manifold leak.

You likely have a bad mass air flow sensor. When this sensor fails, the computer will try to add fuel to compensate, when it can't, it will throw the lean engine codes that you have.

I would not be doing my job however if I didn't mention you could get these same codes from a bad fuel pump. As strange as it might seem, this is why mechanics get paid what they do, these all have to be tested. Now here is a list of the possible causes for your codes.

Possible causes Intake air leaks Faulty front heated oxygen sensor Ignition misfiring Faulty fuel injectors Exhaust gas leaks Incorrect fuel pressure Lack of fuel Faulty Mass Air Flow (MAF) sensor Incorrect Positive Crankcase Ventilation (PCV) hose connection

I hope that you are able to get this resolved, I believe you need a new maf sensor. As for the other code, I wouldn't be to concerned since it's gone.

I hope this info helps you out.