I got a CEL on two days ago, and had the code read at Autozone.

It came out as O2 sensor heater circuit malfunction.



What does this mean? I installed OBX headers two weeks ago and nothing was wrong until now. I pulled out the O2 sensor just now (it's the primary sensor, by the way, not the on in the catalytic converter) and it looks fine visually on the outside.

I had the code reset, and it came back on as soon as I restarted the car.

I'm guessing that the headers are dumping more exhaust gas and unburned fuel, and it killed the O2 sensor. What do you guys think?

I thought it was just reading too rich or something, but my buddy said that it means the sensor is dead. Would the dealership still cover it even though I have headers??

 

did u check to see if the wires were touching the bottom of the tranny pan? they might have melted and shorted the sensor. Happened to me.

 

sensor is NFG...no fukin good!!!
as far as warranty...depends on the dealer. also depends on if the wire harness has been pinched or ripped when installin the headers. some dealers are mod friendly and will replace it but first u must check the harness and make sure the O2 sensor was actually faulty. Good luck

 

hmm

if i remember correctly ron dog had the same problem, i'd drop him a pm if he doent respond to this thread

 

rob
heres what jens wrote me when i though i had this problem but it ended up being the TPS signal


Hey ,
Ok right now with the O2 sensor not functioning properly the ECM is taking an educated guess at what the correct fuel mixture is so driving like this is ok for a bit but you should work to resolve the issue quickly .The O2 sensor that is causing the issue is located on the piece of pipe directly after where the front header and rear header meet under the car .It is a 4 wire O2 sensor .If it is in fact hitting then the correct way to fix it is for OBX to replace the faulty pipe .It is not likely they will do this but it is definitely worth calling them as this is a quality issue not a installation issue .If they refuse to help you can do two things ne remove the pipe and have the bung the O2 sensor is threaded into rewelded to a better position ,or you can attempt to locate a replacment O2 sensor whi8ch has a shorter body than the one in the car .A shorter body will prevent the O2 sensor from striking the pan .Try Bosch and see if they make a direct replacement for your O2 sensor and ask them if they can provide dimensions for it so you can compare this to your O2 sensor .Frankly I feel OBX should step up to the plate and fix this problem with a replacement pipe with the O2 bung inthe correct position .Give em a holler see what they will do than let's take it from there .

Jens

 

Darrin --

Thanks for posting that. But I guess OBX has since made some changes, because the O2 sensor isn't touching anything on my car.

We ran some tests on the O2 sensor and the heater circuit is completely dead. I'll need a new sensor altogether. That's a sumbtich.

 

yea, i wonder what caused it to go out

 

Mine went out,....but I assumed it was from wrapping it up in foil and zip tying it under the car all winter. Or maybe from cutting into the signal wire to send the ECU a narrowband signal from the wideband unit. Either way, I've been driving around for a few months with all the malfunction lights on, as the new sensor sits in the box on the floor in my office. Seems to run fine, but the dash lights are starting to bother me so I'll change it soon.

 

You took the sensor out? I don't know if that's a good idea.

Well, at least in my case, the sensor reader is still working fine. Just the heater circuit died. But if you took the whole thing out and didn't run an O2 simulator, the ECU wouldn't know whether the car is running rich or lean. It would run like crap.

 

ModAddict --

Where are you getting your O2 sensor from? I'm thinking about finding a junkyard and pulling one off a TL/CL, or an Accord if they don't have any. A new Bosch sensor is going for about a hundred bucks.

 

The wideband O2 sensor was installed in it's place and the unit sent a narrowband O2 sensor signal to the ecu, so it was as if the stock one was there.

 

http://www.acuraautomotiveparts.org/ $73.16 plus shipping