o2 sensor heater circuit malfunction?

[ProJect_*A4*]

a week ago one of my ignition coils went out so i replaced all 4.
I also replaced all the plugs since my car was at 100k miles with stock plugs! lol.. i popped in some ngk 6e's and now my car runs great..

i went to autozone to clear my cel light and here are the codes i got

random misfire-p0300
cyllinder 3 misfire
and the last code said...
02 sensor heater circuit malfunction (bank 1 sensor 2) - P0141

I wrote the last part down and cleared all the codes... now i turn to my fellow 'ziners to help me out..

I still think the only reason the last code popped up is because my ignition coil went out and that truly there is nothing wrong.

anybody experiance this before? thanks.

[brewmastr]

that has nothing to do with the coil pack, the o2 sensor has heating element in it to get it up to temp quickly to get the car in closed loop more quickly. the o2 sensor still will function with the heater malfunctioning, it just takes longer for it to heat up so it can accurately measure the exhaust, this will set a code and check engine light unfortunately as it is emissions related. to make this short, replace the o2 sensor.

[doublezero30]

BUMPING this thread instead of making a new one. i got this code 3-4months ago, cleared it, and it JUST came back today. thinking of actually replacing the 02 sensor this time.

question: will this cause a drop in gas mileage? ive seen mine go from about 21mpg to about 17mpg over the past year. also, bank1sensor2 is the rear sensor right? thanks

revo stage 2 turbo back exhaust w TP if that matters.

[jmw241]

I'm with nate, rather than making a new thread I'll bump this one.

Is the failed heater basically saying I need to get a new front 02 sensor?

[old guy]

I'm with nate, rather than making a new thread I'll bump this one.

Is the failed heater basically saying I need to get a new front 02 sensor?

It depends upon what code you are getting. Both the front and rear O2 sensors have a heater circuit. Code P0141 is for the rear sensor heater.

[jmw241]

I'm actually not getting a code, the its the 02 heater readiness.

[doublezero30]

I'm actually not getting a code, the its the 02 heater readiness.

as i said above, when i got a CEL i cleared it in hopes it wouldnt com back...and it took MONTHS for it to come back. thus being said, i bet you eventually will get a CEL. im assuming since youre in RI you regularly drive on the highway? thats usually where the o2 readiness monitors get run. that and on a coldstart.

[absolutegtr]

bumping as I have the same problem, but pertaining to the front sensor: P0030

I replaced the front 02 sensor with a known good (used) one. The code came back almost immediatley. Is there a common wiring issue that is in the engine harness that tends to go bad on these cars? What could cause the code to be thrown if the sensor was the replaced?

[walky_talky20]

If you are questioning a heater circuit code, you can check the resistance of the heater itself at the O2 sensor connector. If that checks out, then plug it in and check the resistance at the ECU connector.

The heater circuit is often easily damaged. If someone was pounding with a hammer on or near the exhuast, that can open the element. Just like a light bulb. Or if the "known good" used sensor was dropped at some point, it may be dead as well.

[absolutegtr]

If you are questioning a heater circuit code, you can check the resistance of the heater itself at the O2 sensor connector. If that checks out, then plug it in and check the resistance at the ECU connector.

The heater circuit is often easily damaged. If someone was pounding with a hammer on or near the exhuast, that can open the element. Just like a light bulb. Or if the "known good" used sensor was dropped at some point, it may be dead as well.

Very true. I wil test out the "new" sensor tomorrow