Check engine light
My car started occasionally stalling out, usually when slowing down quickly for a turn lane. Last week, the check engine light came on. I assumed I needed a tune-up, so I took it to Autozone to buy spark plugs and get the OBII reading… reading said O2 Sensor, Sensor 1, Bank 1 low voltage.
I went to a pull-a-part, found a 2010 Sentra and got an a/f sensor and replaced it. Check engine, still on. Took it to get another reading… Same O2 sensor code PLUS a low voltage code for the speed sensor. I really don't think I did any damage while installing the a/f sensor. Is this likely a p
Experienced mechanics share their insights in answering this question :
Hi there. O2 sensor low voltage can be caused my a number of things. Mass air flow sensor was only one of them. It can be a bad O2 sensor, coolant temperature sensor, or wiring issue.
What should be done is a proper diagnosis for the Check Engine Light. Using a complete scanner rather than just a code reader gives a technician the opportunity to not only read trouble codes, but to read voltages for individual sensors. While a code reader tells you the relevant system that set the Check Engine Light on, but with a number of possible causes, the full scan tool allows checking of each individual cause. Having a proper diagnosis will help you have this repaired correctly without replacing parts that are not faulty.
How to Identify and Fix Common car Problems ?
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A faulty mass airflow sensor is a common reason why a check engine light comes on. If the engine control module receives a MAF error code, it will turn on the check engine light to let you know that there is a problem with the engine.
The mass air flow (MAF) sensor measures the amount of air entering the engine. Check engine light code P0101 is set when the measurement of air entering the engine by the mass air flow sensor is outside of the manufacturer`s specified range.
The Light Stays On
You may think that there is still a problem with the car after the repair, but it`s because the light needs time to reset. The car`s internal computer only resets after a set period where it checks all of its sensors once more. The reset can happen automatically after around 10 to 20 cycles.
The MAF sensor malfunctioning can also cause your car to throw a check engine light (CEL). Furthermore, it can cause different check engine codes such as the O2 sensor, “low air volume”, or something else.
Stalling, jerking, or hesitation during acceleration A bad MAF sensor can cause too much fuel to be left in the combustion chamber, creating untimed detonations. You`ll experience this as poor drivability such as hesitations or sudden jerking motions, particularly during acceleration.
Error code P0101 indicates that there is an issue with your mass airflow sensor (MAF). In this case, the MAF is out of its intended range. Other codes ranging from P0100-P0109, P0505-P0507, and P2096-P2099 often appear simultaneously with this code, given their similar proximate causes.
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.
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.
Leave it disconnected for too long without getting it fixed can start to foul spark plugs and will have other different driving issues. If you need some assistance with this, consider YourMechanic, as one of our mobile technicians can come to your home and replace your mass airflow sensor.
Another common occurrence after the replacement of a faulty MAF sensor is the vehicle not idling correctly or a flat spot on acceleration, leading to the sensor being incorrectly blamed again. It is not uncommon for an engine to run a little rough and not idle properly initially after replacement.
MAF sensors can become damaged, but more often they just get too dirty to do their job well. In this case, they can be cleaned but if it is a mechanical or electrical failure, they must be replaced.
If you unplug the mass air flow sensor the car will start. If you try to plug it in while it`s running the car will die.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
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.
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 circuit + speed sensor circuit…
ANSWER : Hi there. O2 sensor low voltage can be caused my a number of things. Mass air flow sensor was only one of them. It can be a bad O2 sensor, coolant temperature sensor, or wiring issue.
What should be done is a proper diagnosis for the Check Engine Light. Using a complete scanner rather than just a code reader gives a technician the opportunity to not only read trouble codes, but to read voltages for individual sensors. While a code reader tells you the relevant system that set the Check Engine Light on, but with a number of possible causes, the full scan tool allows checking of each individual cause. Having a proper diagnosis will help you have this repaired correctly without replacing parts that are not faulty.
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.
While driving on freeway truck goes into a limp mode, and the check engine light, abs light, parking break light, service brake
ANSWER : It is possible that you could be having an issue with your powertrain control module. This is somewhat of a common problem on many GM vehicles. I would recommend having your vehicle inspected by the dealership to determine if the powertrain control module is functioning properly. If not, a reflash of the powertrain control module may resolve the issue but often times it must be replaced.
2006 Ford Mustang has check engine light on
ANSWER : There are countless potential causes for your illuminated check engine light. The mechanic manually turned off the light, but it came back on because the problem has not been fixed. The first place to start is retrieval of the stored diagnostic trouble codes (DTCs). These codes serve as a starting point for any further diagnostics a mechanic may perform. Codes will be stored anytime the check engine light is on. Since the first mechanic was unable to fix your concern, I recommend giving the professionals at YourMechanic a call. We offer expert check engine light diagnosis and repair.
Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.
Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.
To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.
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.
