P0135: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)

Dec 13, 2008 4 Replies
A

I live in Austin and own a 2001 LS 430 that I bought last year. For the most part, the car has run beautifully; credit to the gentleman that owned it before me.



I took the car in for a state inspection the other day and it failed it -- the fault code was P0135: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1). I do remember my mechanic (Bearden Automotive) mentioned a few months ago that one of my sensors was out and I should get it replaced if I wanted the car to pass inspection -- at the time, I (foolishly) ignored that.



I'd like to get this fixed but I'm trying to save as much money as I can on it. I think I remember being quoted about $350-365 to fix the problem by my mechanic. Is that within the ballpark of what others have paid? How hard would it be to replace the sensor myself?


Vote
Twitter Facebook LinkedIn
R

The price sounds about right. It should not be too difficult to replace the senor yourself, especially since Austin (I assume Texas) is not in the rust belt. Unplug the senor, unscrew the sensor, and reverse the process. If you decide to go with an aftermarket sensor, be sure to get one that has the correct connector already installed instead of getting one that requires splicing wires.

If the old sensor doesn't come out easily, do not force it because you may end up purchasing an exhaust manifold as well. Spray some penetrating fluid like PB blaster, let it sit for a few hours, spray it some more, let it sit some more, and then try removing the old sensor.

After you install the new sensor, you will have to drive the car for a couple of days to get the computer's readiness monitor to be set for the emissions test.

Vote
Twitter Facebook LinkedIn
J

This is a 4.3L 3UZFE engine. Should cost as little as ~$60 to get it fixed if you're mechanically inclined.

Both upstream and downstream sensors (#15733) are as low as $56.79+shipping on

formatting link
This is a Bosch planar type "universal" sensor which you have to cut and splice on the old connector. Follow the instructions and you should be fine. The type with the connector on there costs $20 more each, but looks like you'll get a reboxed thimble from Denso (Bosch is both a supplier and a one- source parts redistributor).

formatting link
Personally I'd much prefer the the Bosch universal even though you have to splice, because it's a new generation of planar sensors. The design means they are more resistant to contamination and "light up" faster than traditional thimble types.

You can borrow the sensor socket from Autozone using their free loaner tool program. Or pick up one for $3.99

formatting link

Vote
Twitter Facebook LinkedIn
R
******************* Bank 1 is the cylinder bank that contains cylinder # 1. I believe that it is on the passenger side (left side from the perspective of standing in front of the vehicle). I've never looked for the sensor, but it will either be in the exhaust manifold or in the exhaust pipe close to the manifold. If you have to reach it from under the car, you will probably have to remove the shield under the engine.

The flat rate time includes time to remove stuck O2 sensors that have rusted in place.

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required