2000 Avalon Check Engine Light..


GreaseMonkey
09-04-2002, 08:26 PM
Help Please...
I have a 2000 Avalon XLS and just yesterday the check engine light
came one. I took it to Auto Zone and got a diagnostic test..and they
told me that my system is too lean and gave me a code: P0171

What does this mean?????

Please help...

phnelson
09-19-2002, 08:17 PM
Just got the Avalon service manual today. (I am trying to track down why my TRAC OFF light is on.

System too lean, means that your gas/air mixture is too light on gas. Possible causes are:

Loose air intake hose or duct
Incorrect fuel line pressure
Obstruction in injector
Heated oxygen sensory malfunction
MAP or MAF sensor malfunction
ECT sensor malfunction

GreaseMonkey
09-20-2002, 04:26 PM
Thanks for your insight..i'll have a friend of mine take a look at it
sometime next week...will update u on that afterwards

GreaseMonkey
09-20-2002, 04:28 PM
By the way, where did u get your Avalon service manual? I need to get one...Thanx

phnelson
09-22-2002, 12:37 AM
Most car parts stores will have them. I bought mine at Amazon.

I'm fortunate enough to work at a junior college that is next door to the Automotive Dept., and they will interpret my codes and reset them for me, or tell me what needs to be done.

Hope this helps

jparkinsonmd
10-11-2003, 07:56 PM
Thanks for your insight..i'll have a friend of mine take a look at it
sometime next week...will update u on that afterwards

Can you tell me what the solution (and problem) ended up being.
Thanks. JP

GreaseMonkey
10-11-2003, 09:41 PM
Hey JP,

Luckily, a friend of mine knew somebody that works for the toyota service center, he said that it was the MASS AIRFLOW SENSOR. Which upon replacing, did fix the problem. I took it to about 5 different shops before that, and they all guessed that it was the O2 sensors. They were wrong of course. There is only one MASS AIRFLOW SENSOR, located on top of the cover of the air filter. GOOD LUCK JP!

ToyotaTech
02-13-2004, 03:30 AM
The trac light will come on when the check engine light is on also to make u look at the dash. and yes the code u had is for a mass airflow meter make sure that u change your air fliter every 15k miles to help this not happen again. Dirt gets on the meter and shorts it out

frowe
08-18-2004, 10:50 AM
Help Please...
I have a 2000 Avalon XLS and just yesterday the check engine light
came one. I took it to Auto Zone and got a diagnostic test..and they
told me that my system is too lean and gave me a code: P0171

What does this mean?????

Please help...
Mine did too. My Haynes manual says it could be one of 6 things 1) Loose intake hose 2) Incorrect fuel line pressure 3) Obstruction in injector 4) Heated oxygen sensor 5) MAP or MAF sensor malfunction 6) ECT sensor malfunction.
Be careful, my 2000 Avalon has a 89465 Airflow Sensor, NOT a 89467 Airflow sensor. My engine must have been made pre or early 2000. Be sure to replace with the correct part!
I have not solved my problem yet, the dang Air/fuel sensor is $388 retail $275 discount! I think I will replace the MAF sensor? You made any progress?

netads
08-23-2004, 06:13 PM
I have a 1998 toyota avalon and when I steer the tires all the way to the right it does not return back to center by itself. I have to steer it back. Does anybody know what might the the mechanical malfunction.

aoluser1
09-25-2004, 04:45 PM
The check engine light came on last night in my 2000 Toyota Avalon.

Many thanks to everyone for contributing so that this morning I tried the following steps:

1. Tighten the fuel cap. The label on my fuel cap indicates that I should tighten the fuel cap until it clicks otherwise the malfunction indicator lamp may come on.
2. Clean the Mass Air Flow (MAF) sensor (and let dry thoroughly) with cleaner for auto electrical parts.
3. Disconnect and reconnect the battery to reset the light.

I don't know whether it was the loosen fuel cap or the MAF sensor causing the check engine light to come on. But it was easy for me to do both step 1 and step 2 above. If you know how to locate the EFI fuse, you don't need to disconnect/reconnect the battery like me to reset in step 3.

I would like to mention one possible factor. A couple of weeks ago, after I took the Avalon to get an oil change, I noticed a burning smell. It turned out that some motor oil was spilled on the magnifold, creating an oily smoke (some of which might end up on the MAF sesnor).

The following link, though not for the Avalon specifically, gave me an idea of how to clean the Mass Air Flow sensor:

http://www.4x4wire.com/toyota/maintenance/tacoma_4runner_30k/maintenancep5.html

Good luck (:)) and make sure you are familiar with the necessary safety precautions before making your personal attempt.

johnsonluke
09-25-2004, 04:58 PM
I have a 1998 toyota avalon and when I steer the tires all the way to the right it does not return back to center by itself. I have to steer it back. Does anybody know what might the the mechanical malfunction.

Did you change or rotate the tires? Remember always change tires in pairs: i.e. either 2 front or 2 rear or all four at the same time. If you change one tire on the front i.e. put a new tire, then that tire will grip the road more and hence will tend to pull the car towards that direction. The solution is change the other tire too. And if you are putting in a single new tire on your car, then always put it at the rear and after 10,000 km you can rotate it to the front.

If the tires are not changed nor new nor rotated, then the alignment may be an issue. take it to a mechanic and for 15 USD per tire/wheel, he will align your car and also the steering. Might take an hour though.

mechanicwannabe
10-06-2007, 06:09 PM
Can anyone tell me exactly how to find the Mass Air Flow sensor in my 2000 Toyota Avalon? I am hoping to clean it as advised in many posts but not positive where it is. I think we found the electrical connector just past the air filter housing but not quite sure where the MAF sensor is. Help!

gunasingh
04-18-2012, 10:25 AM
Hi,

I have a 2000 Avalon XLS and started getting the check engine light. AAA car care diagnosed it to be the air flow sensor and I got them replace it. Then again, it appeared within next 3 days, then AAA diagnosed it to be because of improper gas cover and I replaced with a new one from dealer. Now again I get the check engine light after 3 days. Not sure, what to do now, whether to take it again to AAA or some other mechanic. If anyone has any suggestions, please let me know.


Thanks
Guna

Brian R.
04-18-2012, 11:02 AM
Get the code stored by the ECM. Many car parts stores will read the code for free.

gunasingh
04-18-2012, 06:51 PM
Hi,

The ECM code is P0440. Please let me know how to fix it.

Thanks
Guna

Brian R.
04-19-2012, 02:14 PM
Possible Problems
Fuel tank cap incorrectly installed - loose <= Most common
Fuel tank cap cracked or damaged (Use Toyota part only)
Bad vapor pressure sensor/circuit
Vacuum hose cracked, holed, blocked, damaged or disconnected
Hose or tube cracked, holed, damaged, or loose
Fuel tank/filler neck cracked, holed, or damaged
Charcoal canister cracked, holed, or damaged (collision)

In above description, check hoses between vapor pressure sensor and VSV for vapor pressure sensor and charcoal canister. Also, check the hose between charcoal canister and fuel tank.

Add your comment to this topic!