Code said cylinder 1 misfire, cylinder 2 misfire, o2 sensor misfire?

ANSWER : Without checking the ignition coils and spark plugs myself for proper spark output I would say the engine is misfiring and may be the coils and plugs. It is also common for the valve cover gasket to leak oil into the spark plug tubes shorting the coil and spark plug out so it cannot fire. The check engine light is flashing due to the misfire is active and additional catalyst damage can happen if you keep driving with the misfire and raw fuel dumping into the catalyst. I would recommend having a mobile mechanic like one from YourMechanic come and do a through diagnosis to see if the valve gasket is leaking into the spark plugs and caused damage to the coils and spark plugs. If it is leaking then the valve cover gasket should be replaced with the spark plugs and contaminated ignition coils replaced then computer codes an be cleared and the vehicle road tested for any other problems from driving the vehicle with the engine misfiring.

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.

ANSWER : Hello. The code you have provided is not a valid automotive error code that I recognize. Based on your context I think it may be possible that there is an issue with the signal range of one of your oxygen sensors. If you’ve replaced the sensors then perhaps the issue may be with the wiring. I would carefully examine the wiring to the oxygen sensors, as well as the connector and contacts for any signs of damage, wear, or corrosion. If the sensors and wiring all check out then it may be possible that the issue is with the computer.

ANSWER : Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.

ANSWER : Hi there. What seems to be the issue is the fuel pump is not plugged in. The Oxygen Sensors are working and telling you that the system is too lean with having a low voltage reading. If it was just the upstream sensor, then it would be the wiring, however, both sensors are picking up an issue. This is why the engine is running rough and has no power. If you need further assistance with your vehicle having a loss of power, then seek out a professional, such as one from Your Mechanic, to help you.

ANSWER : As you may know a knock sensor may fail for any of the following reasons:

The knock sensor is faulty and needs to be replaced
There is a wiring open/short/fault in the knock sensor circuit
The PCM/ECM has failed

Any of the above could potentially cause a misfire. The knock sensor should be located under the intake manifold between cylinders #1 and 2.

If you need assistance with this, consider YourMechanic, as one of our mobile technicians can come to your home to diagnose the misfire firsthand and help you fix it accordingly.

ANSWER : Hi there:

It would be best for you to review these two links; the first describes what the P0151 OBD-II Trouble Code is and what typically causes it, and second, the P0131 code and what it means.

ANSWER : This is a tough one because the self-diagnostics on your car are not very sophisticated. The light is on because the ECU is not seeing what it expects at the O2 sensor. When the engine is fully warmed up, there should be a regular sweep from .1 to .9 volts from the O2 sensor about 2 times a second. Replacing the sensor was a good first step, but if there is something about the engine that keeps the mixture from sweeping in response to the sensor voltage, the light will come on. I would check for vacuum leaks first. Then check for any leaks in the exhaust upstream of the sensor. Checking for a ground is good, but be sure that is at the exhaust. Sometimes the exhaust can become electrically isolated from the rest of the car. Some exhausts have a ground strap to prevent this. If you decide you need help with this, contact Your Mechanic. They can send a technician to your home or office to check out your Honda and advise you as to what needs to be done.