my manual is for my integra, but will probaly be the same-obd-2-po135(41)-primary heated o2 sensor heater circut fault.check all the electrical connections.

 

and make sure that air can get in and reach the sensor,also you live in chicago,IL,and it has to reach 600 degrees f before it starts reading the air/fuel mixtures,so maybe its too cold and running on a default mode?

 

Hmm, well it's been fairly warm in Chicago the past few days like over 30 or so degrees and it even went up to 55 degrees one day. It seems to just be because it's cold? Is there any way I can reach you thru AIM or MSN?

 

Hmm, I think I got it now but i'm kind of frustrated because I didn't notice it earlier...

P0135 41 Front Heated Oxygen Sensor Heater Circuit Fault (Sensor 1).
P0141 65 Secondary Heated Oxygen Sensor Heater Circuit Fault (Sensor 2).

I was confusing a P0141 with a code 41, that's probably why huh? Well would I have any drawbacks driving with a malfunctioning heater circuit in my secondary sensor since it doesn't control the A/F mixtures? At least my gas mileage is back up, maybe the primary was going out?

 

I drove with a #65 for two years with no ill effects. The secondary O2 is just there to telll you if your cat is functioning properly, and if it's just the heater circuit that's out, then it'll still work, but it'll just take longer to warm up. You should of course take care of it eventually, but it's not absolutely imperative to do it right away.

 

Thanks a lot. I know what you mean about the secondary o2 sensor doesn't do much anyways. As long as there's no drawbacks like performance loss or long-term effects, I think i'll just wait until I can spare enough money to buy another o2 sensor.

 

You can usually find used OEM 4-wire O2 sensors for about $50, and that should solve your problem. You can also try getting a universal 4-wire O2 and soldering it onto your stock O2's harness. That method worked for my primary O2, b ut for my secondary, I still got the heater code. It finally went away when I replced it with a used OEM O2 that I got.

 

Where can I find the used OEM o2 sensors for $50?

 

Check Classifieds forums, eBay, thepartstrader.com, etc. For example, a lot of the JDM engine swaps that people get include the exhaust manifold and primary O2. People will sell those off if they don't need an extra O2 sensor, and you can use a primary O2 in the rear position without any problems.

 

Thanks a lot!