If I dont change my O2 sensor right away what could happen?

Question

My check engine light came on. The manual says it means there is something wrong with the emission system. My friends say it's probably the O2 sensor and it would cost about $300 bucks. If I dont change it whats the worst that could happen?

Second part of my question is.. What other things could be wrong to make the light go on?

Answer 1

There are in excess of 150 reasons why the check engine light can come on. In most cases its not the oxygen sensor.

take the car to an AutoZone parts store or an AAMCO transmission shop and have them pull the failure code that identifies what's at fault. Both advertize they will do that for free. Once they pull the fault code you can get a better idea of what's wrong and set your priorities accordingly.

If there isn't an AutoZone or AAMCO near you, take it to a dealer. most dealers will not charge you just to pull the code but, like AAMCO they will charge you if additional tests are required. You can just get the code then post a question here to see what it means if you have any questions at that time.

To jump to conclusions is the most expensive thing you can do.

hope that helps

Answer 2

If the MIL light (Malfunction Indicator Light)comes on it can be a permanent or temporary failure of various systems components or sensors. The ECM monitors the PGMFi system per Drive cycle and if the fault occurs twice within one drive cycle it will cause the MIL light to come on. If your vehicle is a pre 1999 Honda normally just by removing the clock radio fuse under hood fuse box for ten seconds will clear any temporary stored codes. Temporary codes can be caused by poor connections or sensors braking down normally temperature related. Permanent codes are normally open circuit wiring, sensors or components and will cause the MIL light to stay on permanently even when you have cleared them. In answer to your original question, the Oxygen sensor is a major contributor to controlling the fuel system and as the other guys have mentioned it will normally over fuel. This isn't a major problem if the car doesn't have a catalytic converter however it will run in limp home mode setting the ECM to basic static setting, reduced performance and poor fuel economy. If it does have a catalyst then damage can occur and they are very expensive on Honda's. If the MIL light is flashing it is the ECM warning the driver that Catalyst damage is likely from the existing fault.
Hope this helps.

Answer 3

I've recently had ANOTHER O2 Sensor go out. This has proven to be critical to the operation of my car. Honda USA has helped me on one occasion of this issue, but is not proving helpful at this time given the current information - we've discovered that the problem with the O2 Sensor going out (this makes time #3) continues to happen because the exhaust manifold is cracked. I will go ahead this weekend and buy not only a replacement oxygen sensor, but also a replacement manifold. The manifold has been accused of continuing to cause the O2 sensor problem, which Honda will not help with, considering their previous help to me.

HOWEVER, if you're cash-rich and can go ahead with the repairs (the Honda repair route - about $300-$400) then do so, and ask Honda that they pay for the cost of the repair (my paid claim was made at 80,000+ miles, so don't worry about the mileage, you won't be the first to make a claim on this issue. It's important for us to realize that we're not the only ones driving Hondas. We're not the first to have this problem, and won't be the last, believe you, me. Our situation is not unique. I only wish that I had waited until I knew that the exhaust manifold was the culprit in the issue of continuously failing O2 Sensors to ask for some financial assistance from Honda. They refuse to aid in payment for the issues this time, since I've received help from them in the past. This time? I'm doing both - If you have trouble with the O2 Sensor, please make sure that they do a thorough check on the engine - perhaps your problem is the same as mine, which was undetected in the first oxygen sensor replacements.

Let me know if I can be of further assistance.

Regards,

Kat

Answer 4

If your car is fairly new then the warrenty should take care of, I think the limit is 80K miles or 5 years.
Your car would use more gas and would certainly not pass the smog test.
02 sensors seldom cost that much, it is worth checking the warrenty first even if you are not the first owner.
Then check with Autoanything.com or Auto zone for best pricing check three places.
It may require a special tool to remove if you can not get a wrench around it, also a universal fit is alot cheaper than a made to fit or O.E.M. unit
Most cars have at least three so make shure the dianostic scanner states which one it is is.
It is an easy R & R job.

Answer 5

worst thing depending on what the car is is that the ecu will stay in "limp-home" mode and you won't have your full power or revs at your control. Or, the car will run rich or lean (usually rich if i remember correctly) and you'll either waste fuel or risk burning your pistons.