My car is throwing CEL P0141 O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2). Is there any connection between my car's coolant going to the reserve occasionally and over flowing causing me to loose coolant? coz of that check engine light ?


quote on this article OBD-II Trouble Code: P0141 Oxygen O2 Sensor Heater Circuit Malfunction (Bank1, Sensor2)

 

Someone may have to correct me here, but I believe the code your car is throwing has to do with the heater circuit for the second O2 sensor. Hence "P0141 O2 Sensor Heater Circuit Malfunction". The O2 sensor on your car is heated electrically (not just by the exhaust). This ensures it gets up to temp and starts reading properly much quicker. That code shows there could be an issue with the circuit that heats your secondary O2 sensor.

You could start by checking to make sure the secondary O2 sensor is properly plugged in. From there, I'm not sure to be honest. There might be a fuse for that...?

I don't think that code has anything to do with you coolant overflowing. How often is it overheating?

 

You overflow tank is over-flowing most likely because either a)you put too much coolant in there or b) your headgasket is blown.

I think the rear oxygen sensor is the least of your worries for now. Have a leakdown test performed.

 

its not overheating.. anymore it just suddenly stopped I have no clue why..
probably my car was running to rich before because I was playing with the fuel settings and ran too rich could that be a factor?

 

and busted my o2 sensor?

 

yea you guys are right. the 02 sensor has 4 wires, 2 grounds and a 12v heater, a 0 -1 volt reference to the ECU/pcm...

The coolant only comes into effect when the temperature of the engine isn't proper. But that's a totally different sensor and has nothing to do with O2...

And it just stopped running? was it a cold start? cause if you have it already rich, and your sensors are ****ed and can't measure then the engines gonna go into OPEN loop and just dump tons of fuel and ignore all the sensors until the engine reaches it's temp (180degrees C roughly)..

So as for the leak down, i'd maybe just change the oil, check the viscosity of it cause i bet the car Hydrolocked from too much fuel and shut you out... kinda like "**** off!" haha.. So there is probably a bunch of fuel in your oil now if you've let the car sit for a couple days...

I don't really know, I'm in school for automotive technician and this is the topic we just started.

Good luck though poor civic

 

I think chris_v2's advice is pretty solid.
If your coolant reservoir tank is overflowing it has nothing to do with your O2 sensor code and you probably have more important problems to look at first.

Also, your car doesn't have to be overheating to have symptoms of a blown head gasket... it may be preliminary signs of a bigger problem to come.