Oxygen sensor light

[mrsboz]

My sensor keeps going off. We get it changed and then it will go off again. The car works perfectly fine. Does anyone know how long these last before the light goes on again so I can get it inspected. I guess I can't get the car inspected with it going on.

 

[msmayor]

Oxygen sensor? Do you mean the "Check Engine" light?

I've never heard of an oxygen sensor light....

If it is the Check Engine light, it normally means there is a problem with the emissions system. First thing I do is re-tighten the gas cap. A loose or broken cap can cause the light to come on.

Other than that, I've always let my mechanic diagnose and fix this problem. I've driven many, many miles with the light on, as my mechanic said its perfectly fine to do so...but it will NOT pass inspection with the light on.

 

[DisneySouvenir]

My oxygen sensor light does the same thing. One way to get it to turn off is to unhook the battery for a while, and then reconnect your terminal. It doesnt reset right away, it has to recalibrate. It generally comes back on, unless the problem persists, after a certain # of miles normally.

I was told it could be caused by not turning your car off during fueling as well.

Have you tried a fuel additive?

My mechanic said the same thing yours did.

No your not losing your mind, but I thougt I was when it happened to me. Nobody has 600$ to throw away.

Hope I have helped

 

[mrsboz]

disneysouvenir - thank you so much. My mechanic said that there is nothing wrong with the car but the light keeps going on. I can't get an inspection sticker with it though. they put in the new part and the light went off but it will keep going on and I can't get a sticker with it and I don't know how long you have to drive without it going on to get a sticker. I don't know what to do. I want to drive my car as long as possible. It is old but runs like a top. How do you get a sticker? By doing the things that you named, which I will most certainly try. The thing is, my mechanic, which is a friend of ours keeps saying we need a new car. If I listened to him I would have "had" to get a new car over two years ago. It is old but I dont' put any money into it and I love it. I get angry when he says I need a new car. It is perfectly safe and rides awesome. I really hope that your suggestions work. I hate to give another car payment to my husband.

 

[buckler]

I have a vague knowledge of this because of a problem I had recently getting my emissions test completed. I had my battery replaced and I had to drive the car for about 60 miles before it was ready to be tested for emissions. Disconnecting the battery or resetting an error code forces you to have to drive the car until it finished testing it emissions systems and says it is ready. There is detailed info here:
http://www.pureenergysystems.com/store/ScanGauge/OBDIITestStatus.htm

Sorry it's technical! I own the Scangauge mentioned in the article so I was able to monitor my car and know when it had finished running the tests and it was ready for emissions testing.

 

[koziclan]

I just went through this situation last week!

Did your mechanic try to pull any codes from the computer? If the light is going on there should be a code.

We have been chasing a problem in my car and hubby erased the error code right before we tried to get it inspected. It failed because when you erase the codes the computer has to reset itself and until it does it won't send any info needed for the emission inspection. Our mechanic told us to come back after we had about 50 miles on it (highway and around town) without any lights. My hubby cleaned the maf (mass airflow sensor) and put 50 miles on and it passed.

 

[darrengs]

There is also more then one O2 sensor.

 

[2Blue1Pink]

We have a 2000 Honda Odyssey with 180,000 miles on it. Our check engine light has been on for years. My husband has had the codes checked and it, too, is an oxygen sensor. Each year, we have the light shut off/reset, drive a bit and then go through emissions. Perhaps it is because of the age of our car, but it passes each time and I don't think it drives long enough to totally cycle through. Once the light came back on as my husband was driving OUT of the emissions station parking lot, but we had already passed. Our moonlighting mechanic has also told us we need a new car, lots of times!!!! Cheers to you for keeping your car going!!

 

[princessmom29]

not going to effect the operation of the vehicle. I would ignore it. Dh's truck does the same thing, and thast is what we have been told to do after trying 4 times to have it fixed. it has been 2 years and no problems.

 

[mrsboz]

I would love to ignore it but I can't. It won't pass inspection with the light on. Thank you though.

 

[3boymthr]

We went thru some problems with this too. Multiple trips to the garage, etc.

I went online and did some research. I found a site that said that aftermarket gas caps can cause air leaks as the seal is not as tight as it should be. Not enough of a vacuum will cause the sensor to go off. DH laughed at me and told me I was nuts but put back on the cap that came with the truck and the problem went away. Come to find out the problem was DHs fancy expensive after market locking gas cap.

We also found out the hard way that you have to drive the vehicle for 200 miles after resetting the sensor or a code is sent at the inspection station which will fail you even though the problem has been fixed. This is a time code/stamp that only time can fix.

 

[BridgetBordeaux]

If the light came on, there is a code and there is a problem.

Even if the vehicle is old, take it to the dealer. They will fix it and warranty their work.

Yes, sometimes the car may seem to run fine, but the code is set because your car is not running as efficiently as it should, or it is "polluting the air" more than is allowed.

There are many reasons why oxygen sensor system may give a code.......and sometimes it has nothing to do with the oxygen sensor itself, but something upstream that is not working correctly.

Once you get the car fixed you can reduce the time for the car to check itself by keeping the car between 1/4 and 3/4 of a tank of gas. Do not fill up the car and do not let it hit "E". Many of the self tests need a specific range of fuel level to conduct the test and 95% full and 95% empty will keep the car from running the tests.

You also have to drive the car under a variety of conditions in order for all the tests to run. Idling, stop and go, and highway trips are needed.

These are the words of my DH.............he handles this stuff for a living.

Good luck!

 

[Shmily1]

I had to have the O2 sensor replaced in my Nissan and it was $90. I was just happy to know what was wrong and that it wasn't major. I traded it after a few years and it was still running great!

Recently, I had/have a Durango. I was told my light was on because I had an air leak in my gas cap. If that's all it was, no problem. I drove it many miles with that light on because it was a locking gas cap from the dealership. FF to this past April. DD18 needed a prom dress so we were going about 70 miles from home to the mall. We made it within 2 miles of the mall and the car ran hot. I probably would have known it was needing attention but the light was still on from the gas cap!! Instead of fixing the light, I can now fix the Durango--by buying a $2500 junk-yard motor (new is atleast twice that!) and then paying to have it put in. I sure wish I would have had that light fixed properly!!

 

[cheap traveler]

I would love to ignore it but I can't. It won't pass inspection with the light on. Thank you though.

Ok, I would need a couple of answers before I could actually tell you what is wrong (what kind of car, what the code is). If they replaced your oxygen sensor multiple times, they could be replacing the wrong one, or like someone else said, it could be a different problem. For example: a misfire, intake air leaks, CAT problem, exhaust leak...

But the best way to try to get "around" the light? Have someone reset your light (with a computer, or just disconnect the battery), then drive your vehicle at least 50 miles, over multiple trips, keeping your speed under 55mph. Most cars O2 sensor monitors run at 55mph.
- A "trip" varies by monitor and car, but involves starting the car, driving a cretain amount of time at varying speeds, and stopping the engine. Best bet - drive normally for a week, but under 55. We get cars through all the time by doing this.


Last note, I promise. If it is one of the "easy" problems like a misfire or oxygen sensor, and you ignore it and keep driving, over time you will destroy your CAT, which costs many hundreds of dollars to fix. Sometimes over $1000.

Good luck

 

[mrsboz]

I appreciate everyone's responses. My car is a 98 Ford Windstar. I wrote about this car about two years ago. The mechanic told me that the head gasket was gone. he told me that I needed to run to buy a new car. I decided to wait to see what happened. Well, I am still driving it to this day.

the light went off. ????? I dont' know why. I had it replaced for $80.00 and it went off at about 50 miles. Well, last night it went off for no apparent reason. My husband is going to bring it to get inspected tomorrow. He had a funeral today. I am hoping that it will pass. The light is off. I couldn't take it to get inspected today because I had several appointments and my husband has to fix one of the headlights. It just has to be screwed in it is loose. I am hoping and praying that the light stays off. Good luck to everyone else with this problem. I will let you know what happens.

 

[kydisneyfans]

Mine has been on solid for 3+ years and nearly 150,000 miles. We don't have inspections here though.

 

[kmacht]

Ok. First of all I would suggest getting a new mechanic or at least having another shop look at your car. There is no such thing on your Ford Windstar as a oxygen sensor light. There is a check engine light though. That light comes on when any number of engine problems occur. The way to find out what it means is to have a mechanic plug a handheld computer device into a port on your car. The handheld unit will spit out a numeric code. You can then look that code up in a book and it will tell you exactly what the problem is.
My suspicion is that the first time this happened your mechanic found an error code for the oxygen sensor. He probably replaced one of the sensors, reset the cars computer and all was good for a little while. Once the car finally re-checked the sensor a number of miles later it came up with the error code again and the check engine light came back on. This could be because of one of two reasons. The first is that your mechanic might have changed the wrong oxygen sensor. There are two of them. One is in before the catyletic converter in your exhaust pipe and the other is after the catelytic converter. If the wrong one was replaced it won't fix the problem. The other possiblity is that your catelytic converter is plugged. The oxygen sensor senses how much oxygen is in your exhaust coming out of the engine. The catelytic converter scrubs that exhaust and gets rid of the bad emissions products. If the catelytic converter is plugged with all those contaminants then it is possible that the oxygen sensor is working fine but the exhaust coming out the back of the catelytic converter getting measured is actaully bad. If both sensors have been replaced this is the most likely scenario.
The reason that your light keeps coming on and off is because the computer in your car resets error codes every once in a while. The light will go off when the code has been reset and stay off until that sensor has been tested again. When it is tested and it shows up as bad the light comes back on.
In any case I would suggest getting this repaired even if you do get it through emissions. A bad oxygen sensor can cause bad fuel mileage and a plugged catalytic converter. If the converter is plugged it can cause even more serious engine damage. A new sensor should cost you around $45 in parts and less than an hour of labor. A new catyletic converter should cost about $400 in parts and 2 to 3 hours of labor. Either way it is cheaper than a few payments on a new car.
As a side note. The 98 ford windstar has a known problem with the aluminum heads warping and causing the headgasket to leak. It isn't good for the engine but you can keep the car running for a while longer if needed. The head gasket keeps the oil and radiator fluid from mixing. When the head warps it lets a little bit of one leak into the other. Just keep checking and changing the oil every 2 to 3 thousand miles and keep a close eye on the ammount of coolant in the radiator overfill bottle.

Keith

 

[mrsboz]

Thank you Keith for your detailed message. I will show it to my husband. I thought that since the light went off we were all set because once it goes on it has never gone off before unless we got it replaced. Now it came back on again. The head gasket must not be gone because my husband checks the coolant all the time and hardly ever has to fill it. The mechanic is a family friend. I am so sick and tired of him telling me to replace the car. I guess he forgets when his kids were younger and money wasn't flowing so freely. The car is older, I'll give him that but it runs like a top. When I ask him point blank why I should get rid of it he has nothing to say. I appreciate everyone who took the time to give me some great answers. I will show them to my husband. he said that he is going to have someone else look at it tomorrow. he has had a funeral/wake the last two days. Thanks everybody.

 

[kmacht]

Oh yeah. I forgot to mention that an oxygen sensor should last anywere from 75,000 to 100,000 miles before needing to be replaced. It definatly shouldn't go bad at 50 miles. Another option you might want to consider if you have one by you is taking your van to either an Autozone, Advanced Auto, or Pep Boys. They have the same hand held scanner as your mechanic and can tell you exactly what the codes from the cars computer are and what they mean. It only takes a few minutes and they will usually do it for free.

Keith

 

[bumbershoot]

I haven't had experience with an older car and the Check Engine light, but I've had experience changing the O2 Sensor! I had a leased VW Jetta, and VWs can be wonky, electrically speaking, and I replaced it a few times in the first two years of having it.

The thing with the Check Engine light is that it can mean SO many things. The mechanic, IMO, *has to* do the diagnostics on it each and every time. Because it could mean nothing, but it could also mean something important. I didn't even have kids, but I drove myself in the car, and I felt that I was important enough to get it checked out just in case it was a real problem.

If you guys are just assuming the light is on for an accidental reason, I just can't imagine that's safe. If he's checking it each time, and he's replacing/resetting it, he should be warrantying his work.

Is he wishing to retire? I think it's odd that a mechanic, whose job it is to fix cars, would want you to get a car that doesn't need to be fixed as often.

If the light came on, there is a code and there is a problem.

Even if the vehicle is old, take it to the dealer. They will fix it and warranty their work.

Yes, sometimes the car may seem to run fine, but the code is set because your car is not running as efficiently as it should, or it is "polluting the air" more than is allowed.

There are many reasons why oxygen sensor system may give a code.......and sometimes it has nothing to do with the oxygen sensor itself, but something upstream that is not working correctly.

Exactly.

Ok. First of all I would suggest getting a new mechanic or at least having another shop look at your car. There is no such thing on your Ford Windstar as a oxygen sensor light. There is a check engine light though. That light comes on when any number of engine problems occur. The way to find out what it means is to have a mechanic plug a handheld computer device into a port on your car. The handheld unit will spit out a numeric code. You can then look that code up in a book and it will tell you exactly what the problem is.
My suspicion is that the first time this happened your mechanic found an error code for the oxygen sensor. He probably replaced one of the sensors, reset the cars computer and all was good for a little while. Once the car finally re-checked the sensor a number of miles later it came up with the error code again and the check engine light came back on. This could be because of one of two reasons. The first is that your mechanic might have changed the wrong oxygen sensor. There are two of them. One is in before the catyletic converter in your exhaust pipe and the other is after the catelytic converter. If the wrong one was replaced it won't fix the problem. The other possiblity is that your catelytic converter is plugged. The oxygen sensor senses how much oxygen is in your exhaust coming out of the engine. The catelytic converter scrubs that exhaust and gets rid of the bad emissions products. If the catelytic converter is plugged with all those contaminants then it is possible that the oxygen sensor is working fine but the exhaust coming out the back of the catelytic converter getting measured is actaully bad. If both sensors have been replaced this is the most likely scenario.
The reason that your light keeps coming on and off is because the computer in your car resets error codes every once in a while. The light will go off when the code has been reset and stay off until that sensor has been tested again. When it is tested and it shows up as bad the light comes back on.
In any case I would suggest getting this repaired even if you do get it through emissions. A bad oxygen sensor can cause bad fuel mileage and a plugged catalytic converter. If the converter is plugged it can cause even more serious engine damage. A new sensor should cost you around $45 in parts and less than an hour of labor. A new catyletic converter should cost about $400 in parts and 2 to 3 hours of labor. Either way it is cheaper than a few payments on a new car.

I agree with all of that as well. Even the stuff that's perhaps a bit above my head.