Help with P1135 code

[GearUP]

Hey all, I just changed the front oxy sensor in my 2002 to fix the p1135 code. I disconnected the battery, unplugged the ECM fuse like another post suggested, and then put in the new Denso sensor. The check engine and VSC TRAC lights went out for a good week or so, but all of a sudden they are back. I'm ticked off because I thought the new sensor would fix it and I was about to get it registered here in CA since I just moved. Any help is much appreciated...

 

[jgue467]

Did you check for an open or shorted out circuit between the sensor and the ECU?

That is the first item to check, if ok then replace sensor heater. If that doesn't work then it's the ECM according to the FSM. Luck. :cowboy:

 

[GearUP]

I assume the circuit is good since the lights stayed off so long. I've had the code for a long time and in the past when I tried clearing it with a code reader it was back within a few miles. I'll get under there and check it out though. Are you saying the whole ECM might be bad? I don't wanna know what that costs...

 

[Nate_GB]

Where did you buy the sensor? Is it OEM or OEM equivalent (denso)? I think a wiring or ecu issue is less likely than a cheap replacement sensor that failed prematurely. Of course, if it's a denso sensor, you'd want to do some more investigating.

 

[GearUP]

Got it off amazon, Denso 234-9002. Not a knock off or anything either, came in a Denso box with Denso markings

 

[Nate_GB]

Got it off amazon, Denso 234-9002. Not a knock off or anything either, came in a Denso box with Denso markings

Since it's Amazon and they're awesome, I would probably return the sensor and say it was faulty and order another one and replace it again. That way you are nearly 100% sure it's not the sensor before chasing a wiring or ECU problem.

Or you could ohm out the sensor before sending it back to confirm its good. Fsm says resistance between terminals +B and HT of the sensor should be between .8 and 1.4 when the sensor is cold and 1.8 and 3.2 when the sensor is fully hot after driving.

 

[TheDurk]

Hey all, I just changed the front oxy sensor in my 2002 to fix the p1135 code. I disconnected the battery, unplugged the ECM fuse like another post suggested, and then put in the new Denso sensor. The check engine and VSC TRAC lights went out for a good week or so, but all of a sudden they are back. I'm ticked off because I thought the new sensor would fix it and I was about to get it registered here in CA since I just moved. Any help is much appreciated...

Did you reread the code? Or are you going by the fact the light came back and assuming it's another P1135? I can't tell from your post.

Because you fixed a P1135 and now your front sensor works. So NOW your ECM can run its catalytic converter test. So you might well have P0420 or other code that indicates some other problem the ECM didn't know about because it didn't run the test. Read the code before you return the sensor, for Pete's sake. The lights staying out support this. A P1135 from a bad sensor out of the box would have come right back in a minute or so. The fact it took a week suggests it's something else, with P0420 my wild-ass guess.

The ECM is always the last item on any trouble list--all of them. It rarely turns out to be the cause.

Anyway, I don't think even Amazon does returns on electrical sensors.

 

[GearUP]

Turns out I'm not the sharpest tool and assumed it was a return of the same code. Went back as you suggested and had the codes read and I'm now getting P0440, P0441, and P0446... I've done some light research so far and found this one is going to be hard to chase down, possibly resulting in a charcoal canister change.

Anyone experienced this on their runner? If so what fixed it? Thanks as always for the help!