jlajara

I have a 2001 es 300.
Engine & Trac icons came on recently.
Auto Zone said code was P 1155 (Bank 1 Sensor 1).
Where is this sensor, & best way to remove & replace?

Hayk

iTrader: (1)

Often times, it's a combination of things that's triggering a CEL. I would have a mechanic diagnose your car first, and see if the O2 sensor is really at fault.

tomf

Bank 1 sensor 1 a/f/ration sensor is located next to the firewall. When I replaced mine I attacked it from the bottom of the car. I've heard of some people being able to reach it from the top/side. I'd use the Denso replacement. They are the OEM manufacturer. Screw out the sensor and un-clip the connector. Reverse to install. You'll probably need a O2 sensor socket to remove it. The hardest part is reaching the sensor and connector.

jlajara

Just a word of appreciation for the information provided.
I will confirm the need to replace the air/ fuel sensor and if necessary replace it as suggested.

EEngineer

reset the code first and see if it goes away.

GoodRevs

I just posted about this, make sure you have the right bank.

jlajara

Thanks
What about Bank 2 Sensor 1? Where is this found?

PFB

That one is the easiest one to change. It's located on the exhaust manifold, right behind the radiator fans. Easily visible and reachable from the top. Plenty of room to work in. With the right tools it should not take more than 20 minutes to change.

jlajara

Thanks a million!
Had the code read at AutoZone once again; it was P1155 Bank 2 Sensor 1(in front of Radiator on Exhaust Manifold).
I purchased it at AutoZone & replaced it within 15 minutes with my 22mm open end wrench.
I reconnected the battery & dash "Engine & TRAC" icons have not returned after 75 miles.
Word of caution!
Buy the Denso Brand, not the Bosch Brand; the Denso Brand fits perfectly!