Where's the O2 sensor?

CJORDAN22 · #1 (**permalink**) 03-12-2006, 07:32 PM

I have a 2000 avalon. My check engine light is on and the code showing is P0171 - Fuel Trim System Lean - Bank 1.
Where can I find a diagram of where to locate the Bank 1 O2 Sensor? I would also like to know where the MAF is. Any suggestions?

nhparrot · #2 (**permalink**) 03-12-2006, 09:59 PM

Quote:

Originally Posted by CJORDAN22

I have a 2000 avalon. My check engine light is on and the code showing is P0171 - Fuel Trim System Lean - Bank 1.
Where can I find a diagram of where to locate the Bank 1 O2 Sensor? I would also like to know where the MAF is. Any suggestions?

see attached

CJORDAN22 · #3 (**permalink**) 03-13-2006, 01:08 PM

Wow, thanks for the awesome diagrams. Can I access those documents on my own with my TS subscription?

nhparrot · #4 (**permalink**) 03-13-2006, 02:28 PM

Quote:

Originally Posted by CJORDAN22

Wow, thanks for the awesome diagrams. Can I access those documents on my own with my TS subscription?

Only on this forum.

burninc · #5 (**permalink**) 05-05-2006, 03:14 PM

i have a 2000 avalon and bought a universal O2 sensor. I need to know what the original wires do? Heater, ground, ect.

mustang67408 · #6 (**permalink**) 05-05-2006, 07:09 PM

Quote:

Originally Posted by burninc

i have a 2000 avalon and bought a universal O2 sensor. I need to know what the original wires do? Heater, ground, ect.

A code P0171 IN THIS VEHICLE is usually a Air FUEL SENSOR/MAF sensor/vacuum leak or low fuel pressure. I would say its the AIR FUEL SENSOR in bank 1. (Thats the bank closest to the firewall w/cyl #1 in it).
The universal 02 sensors dont usually work.
The Factory ones are not that much more expensive than the aftermarket ones and they work a whole lot better.

The 2000 Avalon uses 2 Air fuel sensorS in the exhaust manifolds(Bank 1/2) before the cat converter.
It has a 02 sensor AFTER the cat, this will not cause a P0171
The air fuel sensor is approx $155 from Toyota.

burninc · #7 (**permalink**) 05-06-2006, 05:41 PM

Thanks for the info. Unfortuately I found out the hard way that O2 sensors don't work up front.

CJORDAN22 · #8 (**permalink**) 06-05-2006, 06:31 PM

I replaced my Bank 1 sensor about a year ago and it seemed to solve my problem but now I'm getting the P0171 code. NOTE: The sensor I bought a year ago was not purchased direct from Toyota. Other than the engine light being on, the other noticable problem is bogging down when I punch the gas pedal, no acceleration.
Would you recommend replacing the Bank 1 sensor again with a direct from Toyota part? Or should I check something else?

mustang67408 · #9 (**permalink**) 06-05-2006, 07:04 PM

Quote:

Originally Posted by CJORDAN22

I replaced my Bank 1 sensor about a year ago and it seemed to solve my problem but now I'm getting the P0171 code. NOTE: The sensor I bought a year ago was not purchased direct from Toyota. Other than the engine light being on, the other noticable problem is bogging down when I punch the gas pedal, no acceleration.
Would you recommend replacing the Bank 1 sensor again with a direct from Toyota part? Or should I check something else?

I would recommend cleaning or replacing the MAF sensor. If you have an aftermarket air filter, I would recommend returning it to stock. A dirty or bad MAF will cause the BOGGING DOWN problem your experiencing

CJORDAN22 · #10 (**permalink**) 06-17-2006, 02:40 PM

Hey Mustang, you were right on. I put in a new MAF sensor and everything is back to normal. THANKS!

mustang67408 · #11 (**permalink**) 06-17-2006, 03:27 PM

Your welcome.

TS ROCKS!!!

cs2634 · #12 (**permalink**) 09-05-2006, 03:19 PM

i have a 2001 avalon and my check engine light is on code p1155,i was told its the af sensor on the left side,does any one know if this is right and is that the one in the front exhaust manifold by the radiator,thanks

mustang67408 · #13 (**permalink**) 09-06-2006, 12:47 AM

Quote:

Originally Posted by cs2634

i have a 2001 avalon and my check engine light is on code p1155,i was told its the af sensor on the left side,does any one know if this is right and is that the one in the front exhaust manifold by the radiator,thanks

Yes it is the upper one near the radiator.

braveheart3158 · #14 (**permalink**) 10-12-2006, 04:33 PM

I have a 2000 avalon. Recently got codes po171 po1130 and po 1135.

Dealer says it is the o2 sensor in the back. he also said it is seized and will not come out. Dealer may need to change manifold. I took the car back.

The cost to change manifold would be $1600. Change the o2 sensor $450. I would like to attempt to change it myself.

Wich one do I change as per the code above? I believe at this point it is the one near the firewall. Can this be confirmed?

Whats the best way to access this one? From under the car?

How can I remove a siezed one? If it is really siezed.

braveheart3158 · #15 (**permalink**) 10-18-2006, 06:25 PM

Quote:

Originally Posted by braveheart3158

I have a 2000 avalon. Recently got codes po171 po1130 and po 1135.

Dealer says it is the o2 sensor in the back. he also said it is seized and will not come out. Dealer may need to change manifold. I took the car back.

The cost to change manifold would be $1600. Change the o2 sensor $450. I would like to attempt to change it myself.

Wich one do I change as per the code above? I believe at this point it is the one near the firewall. Can this be confirmed?

Whats the best way to access this one? From under the car?

How can I remove a siezed one? If it is really siezed.

HELP! Is any one there?
A follow up questions---
1-Does it matter what order the codes came in?