O2 sensors changed, but check engine light still showing code after clearing it I checked fuse. Wires are good and used Denso OE.
Check engine light was on for o2 sensor behind the cat. Found it to only have 1 wire out of 4 connected. Went ahead and changed all of the o2 sensors with Denso OE direct fit o2 sensors. I then checked the o2 sensor fuse and replaced it since it was blown. Then I did an oil change and changed the air filter. After 5 minutes of driving the check engine light came on and the car felt as if it was shaking / misfiring again. Now the codes have reappeared and include a general misfire. I've check all the wires and they are good. The sensors are brand new and exact replacement. And the fuse has
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Depending on what the code was for will determine if the oxygen sensor was to be replaced. If the conditions were for a rich or lean mixture and it said oxygen sensor, then the spark plugs and wires could need replaced if its a rich reading or the fuel injectors could be clogged or not working if its a lean mixture. If the code said that the oxygen sensor was bad, then check the harness and see if there is a break in the wiring or a short to ground in the wiring from the oxygen sensor to the main harness. If you need further assistance with your check engine light being on, then seek out a professional, such as one from Your Mechanic, to help you.
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If the mechanic completed the O2 sensor replacement, reset the codes and the error code was triggered again, it is possible that the catalytic converter is damaged and needs to be replaced.
This condition is easily achieved by letting the car sit overnight. The ignition key must not be left on prior to the cold start. Otherwise the heated oxygen sensor diagnostic may not run. Start the engine and idle the engine in drive for two and half minutes, with the A/C and rear defroster on if equipped.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
It could be due to a part that`s failing in your fuel system. If an oxygen sensor or mass airflow sensor is failing, it could give incorrect data to your engine`s computer, causing the misfire. When a vacuum line is broken, it can cause a fuel-injected motor to misfire.
You don`t “reset” the computer. You just clear/erase the memory code and all is well in the world. If the repair was done properly the check engine light will stay off unless there is another concern.
Disconnect both O2 sensors (front and rear). Start the engine and allow the vehicle to idle. After faults have stored: Cycle the ignition OFF/ON 2 times with a 10 second pause in between key cycles.
Usually a reset is performed after 2–3 drive cycles after the problem has been repaired. I have had drive cycles complete after about a 3 miles test drive and then on other vehicles, it took 20 miles.
The catalytic converter, or cat for short, is responsible for removing harmful emissions from the exhaust. If the two O2 sensors collectively sense that the oxygen levels don`t change significantly after running through the cat, it`s a sign of a bad catalytic converter.
The most common causes of misfires are worn, improperly installed, and mishandled spark plugs, malfunctioning ignition coils, carbon tracking, faulty spark plug wires and vacuum leaks.
Generally, the cause of a misfire at idle is an incorrect air-fuel mixture. This can be caused by a faulty O2 sensor, a fuel injector that needs cleaning, or even vacuum leaks.
So why is the light still on? Here`s something you probably don`t know: after clearing the car`s computer you will need to drive for about 50 to 100 miles. As you drive your car the computer will monitor all the sensors and register the results.
Usually a reset is performed after 2–3 drive cycles after the problem has been repaired. I have had drive cycles complete after about a 3 miles test drive and then on other vehicles, it took 20 miles.
The check engine light should go off after you drive for several minutes if the light was caused by a loose gas cap. Pay attention to the dashboard after the check engine light experience. If you find that the light keeps coming on, and goes off again once you tighten the gas cap, then your gas cap is too loose.
To make sure the check engine light does not reappear, it`s recommended that you drive your car 30 to 100 miles. This enables the vehicle`s “Drive Cycle” to reset, as the various sensors need time to recalibrate.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
O2 sensors changed, but check engine light still showing code after clearing it I checked fuse. Wires are good and used Denso OE.
ANSWER : Depending on what the code was for will determine if the oxygen sensor was to be replaced. If the conditions were for a rich or lean mixture and it said oxygen sensor, then the spark plugs and wires could need replaced if its a rich reading or the fuel injectors could be clogged or not working if its a lean mixture. If the code said that the oxygen sensor was bad, then check the harness and see if there is a break in the wiring or a short to ground in the wiring from the oxygen sensor to the main harness. If you need further assistance with your check engine light being on, then seek out a professional, such as one from Your Mechanic, to help you.
check engine light O2 sensor already replaced same codes still popping up after replacing old O2 sensor
ANSWER : Hi there. What you received from the parts store was a code retrieval, not a diagnostic. The codes are set when a fault is detected against normal operating parameter. The computer does not know what caused the fault, only that the fault meets the criteria for this code to set. There could be a problem in the wire harness, converter, or the ECM. The code and data are needed to properly assess the direction that a diagnosis needs. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.
Diagnostic code read o2 sensor bad, replaced o2 sensor, cleared code but engine light came back on, is it caused by bad air filter
ANSWER : Hello there. Typically jump starting a vehicle doesn’t trigger an OBD-II error code. However, one of the most common misdiagnosis issues with the P-2270 is replacing the O2 sensor before diagnosing if there are any exhaust leaks. Obviously, you’ll want to check for the exhaust leaks first, repair the damaged component, and then clear the codes before scanning the vehicle again. Sometimes the electrical harness attached to the O2 sensor is damaged or dirty which will also trigger this error code. The noise and vibration may be an indicator of a loose exhaust pipe, which may be the source of the error code staying on. If you need any help, have a technician from YourMechanic come to your home or office to diagnose your Check Engine Light and make the necessary repairs.
Service engine warning, MAF code and O2 sensor code, along with check suspension light are turned on
ANSWER : Hello, it sounds like you have quite a few things going on. I am going to do my best to break them down for you.
First if the engine is very loud when idling and the belt has already been replaced, there may be an issue with the tensioner or idler pulley.
Next, the Navigator is known for needing service to the air suspension system as it gets up in miles, the most common causes of these are the air struts themselves have failed, or one of the air lines has a leak.
Lastly, if the O2 sensor and MAF are continually coming back after the sensors have been replaced, the most common cause would be either an exhaust leak or a vacuum leak.
Qualified technicians such as the ones at YourMechanic will be able to diagnose these issues and recommend the best path to repair, starting with a diagnosis of your warning lights.
So I had two codes come up for two of my o2 sensors..replaced them both and check engine light is still on…my mechanic seems to
ANSWER : Hi there:
Although it’s hard to say if there was serious damage done to your ECM during this service, it’s more likely that the stored error codes were never cleared from the ECM, and that’s why the warning lights still appear. This is a common oversight with some mechanics, but if you have a mobile mechanic complete a check engine light inspection, they should be able to clear those stored codes and determine if further damage has occurred.
p0011 code,check engine light one, changed bank 1 vvt solenoid and check engine light still on?
ANSWER : The P0011 code is typically caused by oil issues with the car. I would particularly make sure the engine oil level is not low. The VVT solenoid relies on proper oil levels to do their job. If they don’t have enough oil, they won’t work. You can have a mobile technician from YourMechanic visit your home or office to inspect the Check Engine Light for you. If you follow through with a repair with us you will be reimbursed for the cost of inspection.
P2196 OBD-II Trouble Code. came and went in 24 hours. 4 starts.
ANSWER : If the mechanic tested the output (functioning) of the oxygen sensor, especially according to the protocol at this link and found that the sensor was non functioning at that time, what you might be experiencing is a "failing" oxygen sensor and so the latest instance of Code P2196 might be explained by that. A complexity though is Code P2196 has many causes other than a failing oxygen sensor including: a faulty fuel pressure regulator; MAF (Mass Air Flow) sensor; ECT(Engine Coolant Temperature) sensor or damaged ECT wiring; leaking or stuck open fuel injector or injectors; and spark plugs and/or coil pack. Basically, if the Code (P2196) recurs, the oxygen sensor output can be re-tested but the mechanic will hopefully be aware of all these other possible causes of that Code setting. If the Code recurs, you can request a check engine light diagnostic and a certified Mechanic, dispatched by YourMechanic right to your location, will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
I changed my camshaft already and erase the code to turn off my check engine light, but the light still comes on after 30mins.
ANSWER : Replacing the camshaft requires nay adjustments to various other components to properly ensure that the timing is set correctly. When this is done there are various sensors that monitor camshaft position and speed to control timing and fuel. When this is not done correctly, this can result in additional check engine codes and cause the car to not start. I would recommend having an expert from YourMechanic come to your home to diagnose the Check Engine Light definitively and make repairs.
