How do I replace an oxygen sensor of a VW Golf 5 and where is it located?
One thing I’ve discovered while learning to work on my own car is that Google is definitely your friend! People who work on cars, and companies that sell you parts, love to post information about specific auto repair tasks. All I did was search for “o2 sensor vw golf mark 5” and this was the first hit. I opened it and it looked reasonable. I’ve never worked on a Golf (though my mentor Quentin has) so I haven’t checked the information myself.Oxygen Sensor Replacement
How long to replace oxygen sensor is car?
Don't forget that many garages charge for the part-hour, so even if the job runs to 1 hr 13 mins, you get charged for two. Oxygen (Lambda) sensors are not hard to fit, but the old ones can be a real pain to get out, the extreme heat fuses them in place and so sometimes require removal with serious focussed heat to get them out. Even then they can shear and then you have to take the entire section of exhaust out to remove the broken part. 2 hours to do two Oxygen sensors, to me at least, doesn't seem unreasonable.
How urgent is it to replace the oxygen sensor on a car when it causes the check engine light to come on?
So our car's check engine light came on and the computer at our local autoparts store says the oxgen sensor may be bad. Is this something we should replace asap, or can we wait a week or so to do it?
Should I replace both O2 sensors?
Always replace everything in pairs or in sets. By not doing so you will have to replace everything at a different time. Also just because a cars codes are flashing a particular code, does not necessarily mean that the sensor has gone bad. It could be a secondary item like a fuse or other related to the same sensor. For example: I had a 1987 Chevy Camaro Sport Coupe, that kept flashing that the Mass Air Flow sensor was bad. I paid nearly $200 on a new sensor. Erased the code and drove it down the road about 12 miles and the light came back on. Turned out after trial and error and arguing with the auto parts store, the problem was a little 15 amp fuse that was housed in a black in line fuse holder, had been blown for nearly a year. The fuse was 10 cents to replace. I felt so dumb. Do process of elimination, before you spend a bunch of money so you don't waste it on the wrong part. Also it is a good idea to replace the Oxygen sensors every two years. They act as fuel regulators to adjust the amount of fuel the engine is using. Again, replacing them every two years is like a tune up as well. You will get better fuel mileage and get lost power back.
After you replace an oxygen sensor will the check engine light turn off automatically?
No the light will not turn off right away. You can disconnect the negative terminal on the battery for 10-15mins, or take the car to an Autozon or Advance auto parts and they will reset the light for free.
O2 sensors are bad do I really need to replace them?
If the O2 sensors fail, the car is suppose to go into open loop mode. Which basically means the engine is suppose to have some nominal values set in the program and is suppose to use those values instead of values from a feedback loop. The feedback loop as explained by others helps control the amount of fuel that is injected into each of the cylinders. Without the feed back loop, the engine doesn't know how much fuel should be exactly injected and injects a nominal set value. Typically the nominal value (value with out feedback) is not as good as a value with feedback. Imagine walking across a room full of stuff with your eyes closed and not hitting anything, and walking across the same room with your eyes open. Your eyes will help you do a better job because they give your body feed back on what to do to avoid objects. However you legs can still get you across the room even if you bump into a few things. If your O2 sensor doesn't work, then you're forcing other parts in your car to work harder. (Just like when you bump into something, you'll know somethings was there and turn). Well in most cases if the O2 sensor is not working properly, excess fuel is injected into cylinders and this reduces fuel economy. It also makes the Catalytic converter work harder, and could cause it to deteriorate faster. ($300 to replace) So in the short term you can drive with bad O2 sensors, but not recommended if you plan to keep the vehicle. Check to see if the vehicle is still under warranty. A 2002 Ford might still be under warranty. I'm not sure if the Taurus had a 3 year or 5 year warranty for emissions related devices. Most vehicles have a minimum of a 5 year emissions warranty and you might be able to get the O2 sensors replaced under warranty.
Do i have to replace both o2 sensors?
I have a 99' jeep grand Cherokee, and well my fuel milage has went down dramatically. From about 18-19 miles to the gallon to like 9-10. I just did a tune up on it, so my brother recommended changing the o2 sensors on it, since milage went to crap and black smoke comes out my exhaust when accerating. My question is do I have to replace both upstream and downstream at the same time? Or can I just replace the upstream since the downstream is more for the cat. Converter. They are 70$ a piece and I'm kinda on a budget, being a single mom of 2 and going thru a divorce. So money is kinda tight. So I'm just wondering if I can just replace the upstream and not worry about the downstream for now.
O2 sensor. What happens if i don't replace it?
This can cause problems. The O2 sensor lets the computer know if the fuel air mixture and ignition timing are correct by measuring the exhaust gasses. Without this information the computer will use a static pre-set value to keep the engine running. Your engine could be running rich and the computer would not know this. If the engine is running rich the unburned fuel gets burned in the catalytic converter where it does you absolutely no good. But this isn't the problem. The problem is that this can cause the catalytic converter to over heat. The materials inside will melt and block the catalytic converter. This destroys your expensive catalytic converter. With the blocked exhaust you will have all sorts of driveability issues. The engine will run like crap and have a very noticeable loss of power. It will not idle. It may run hot. Better to replace a $35 O2 sensor now than to replace a $400 catalytic converter later.