Check Engine light comes on randomly now, not happy about it

I drive a 2010 Honda Pilot with 44,000 miles on it. The Check Engine light was popping on every couple of days, but nothing consistent. I finally got my car checked and it turns out the spark plugs were faulty, which was causing my problem. I replaced them 5,000 miles ago but now I am having a similar issue again. How should I proceed? Just keep replacing the plugs?
Experienced mechanics share their insights in answering this question :
I would recommend going back to the person that replaced the plugs to see if there is a warranty issue for the repairs needed. You will need to have the vehicle’s computer scanned as well as diagnosis of any codes. If a code P0300 to P0306 is received, then it is a misfire to a particular cylinder. If other codes are received, then the failure you are having now may not be for the same reason you had plugs changed originally. I recommend a thorough diagnostic check and if a single plug is fouled out, get a diagnostic on that particular cylinder to find out why it is fouling the plug out. Pay attention to any other issues that may contribute to the plug fouling. Look for things like excessive oil consumption or loss of fuel mileage. This would help YourMechanic on any diagnostics to be done.

How to Identify and Fix Common car Problems ?

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But, there are other possible causes of intermittent illumination of the Check Engine Light such as failures in engine sensors, intermittent misfires, and faults with sticky or stuck valves such as in the EGR (exhaust gas recirculation) system or the EVAP system.
Worn/failed spark plugs, coil packs, or spark plug wires can trigger your check engine light to come on. In today`s cars, say Firestone Complete Auto Care technicians, if a plug starts to fail then the most obvious event should be the check engine light coming on or even flashing.
The reasons for a check engine light turning on can range from something minor like a loose gas cap to something more serious like a faulty catalytic converter. It could even be a sign of internal engine failure. Ignoring the problem can turn a potentially quick fix into a costly and time-consuming repair.
Honda Pilot Check Engine Light Flashing

Other common reasons for a Check Engine Light are a malfunction with the fuel injection system, faulty head gasket, dirty mass airflow sensor, damaged oxygen sensor, faulty emissions control part, or defective spark plugs to name a few.

Will your check engine light turn off by itself? In most cases, successfully repairing the issue that caused your light to come on will cause the check engine light to turn off automatically—but only after 10 to 20 “cycles”.
These problems can range from faults within the electrical system, the engine, fluid levels or to problems within the car`s emissions system. The problem can even be as simple as forgetting to tighten your gas cap – in fact, this is the most common reason why check engine lights appear in the first place.
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.
Check your gas cap first. Many vehicles have a loose gas cap indicator that will be triggered before your check engine light comes on. If your gas cap is loose or the seal is not tight, the vapor leakage can cause your fuel system to trigger the check engine light.
Failing Oxygen Sensor

One common issue that can cause your check engine light to turn on is a failing oxygen sensor. The oxygen sensor is responsible for monitoring the amount of oxygen in the exhaust system, and if it detects a drop in oxygen levels, it will trigger the check engine light.

This is a sign you should stop driving and have your car looked at by a mechanic as soon as possible. Use your best judgment on whether to call a tow truck or drive yourself to a nearby repair shop. Is the light flashing? In many vehicles, there are two types of check engine lights—a solid light and a flashing light.
An emission system warning light indicates a problem with the mixture of fuel to air in the engine. In the Honda Pilot, the fuel injectors can go bad between 40,000-60,000 miles. An oxygen sensor near the catalytic converter may need replacing as well.
It is possible that your automobile`s check engine light has come on because of a false alarm. This being said, if the engine control module (ECM) turned on the check engine light for no reason, the ECM could be malfunctioning itself. This crucial part is the heart of your automobile.
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.
If your engine is misfiring, you may be able to fix the problem easily by replacing your spark plugs. Spark plugs are relatively easy to remove from engines and inspect for damage, and at less than $25 a piece, they are relatively cheap to replace, too.
Even if you`re not having problems you`ll still want to have your spark plugs changed out at every 30,000 mile interval. For most drivers, that will mean that you`re due for spark plug service once every 2-3 years!
Misfires don`t simply go away – they need to be addressed immediately. Even if they don`t get worse, they certainly won`t get any better unless you take the car to a mechanic.
A clogged or failed exhaust gas recirculation or crankcase ventilation valve or faulty oxygen sensor can send the wrong signals to the computer and cause misfires.
If left untreated, a cylinder misfire can lead to significant engine damage. Worse, if you experience a bad misfire while driving, it could result in an accident. This is why it`s important to treat engine misfires as soon as you detect them.
Repeated overheating of the spark plug tip can cause the plug to prematurely fail. Overheating can be caused by many things like pre-ignition and a malfunctioning cooling system. Pre-ignition can lead to heat building up in the combustion chamber causing the spark plugs to fail.
1) Check your gauges – Look for an indication of low oil pressure or that your vehicle is overheating. If either of these issues are present, turn your vehicle off to prevent any further damage. 2) Inspect the condition of the battery and charging system – If you lose power from the battery, your vehicle will die.
The emissions/exhaust system is the most likely culprit for many check engine lights being illuminated. There could be an exhaust leak or a problem with the catalytic converter. The mass airflow sensor (MAF) is another sensor that is easily tripped or can fail.
Yes, a bad spark plug can confuse your car`s internal computer and trigger the O2 sensor code.
Oxygen sensors are a common cause of “check engine” lights. This sensor is located in the emission control system of your car, and is standard on all vehicles manufactured after 1980. The oxygen sensors are used to ensure that your engine is burning the correct amount of fuel, and running at peak performance.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Traction light/reduced engine power and check engine light coming on
ANSWER : Hello. From what you describe, it would appear that your vehicle may be experiencing some sort of intermittent wiring or sensor issue. If the problem occurred again after driving over a bump, then it may be possible that a damaged or loose wire is shorting or having contact issues. A common issue that can cause stalling is a faulty crank position sensor or wiring. I would carefully examine the engine for any loose or damaged wires. If the Check Engine Light comes back on, I would recommend having the trouble codes scanned before resetting the computer.

Check Engine Light comes on after starting pickup
ANSWER : Hello there, thank you for asking about your 1992 Isuzu Pickup. A professional will have the correct equipment to read OBD1 codes. Retrieving the diagnostic trouble code(s) is the first place to start when diagnosing your vehicle. Increasing RPMs changes engine load, which can in turn affect many different sensors and components, causing the Check Engine Light to illuminate. The only way to narrow down the options and find the culprit is through in person diagnosis with an OEM compatible scan tool. A certified technician from YourMechanic can retrieve the OBD codes at your home or office.

I am not getting any power when I turn the key to the on position. there is no dash lights only check engine lite comes on.
ANSWER : The problem of having erratic electrical issues with this year Bronco they have problems with the ignition switch losing contact. You should check and replace the ignition switch. When the switch is removed you should check linkage rod and electrical connector for problems and repair as needed along with replace the ignition switch.

Car goes into limp mode when the check engine light and VSA light comes on
ANSWER : The lights that you have on and the vehicle going into fail safe mode is an indication you have a major system failure that will require computer to be tested for codes first. There are many possible codes it can be so the additional testing will be needed to isolate the cause of the problem.

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.

Battery light goes on when I start car then turns off, if I rev engine light comes back until rpms go down. Abs goes comes on/off
ANSWER : Batteries can die due to faults in the charging system so ideally a suspected "faulty" battery should be load tested before a decision is made to condemn it. The only exception to this rule is if the battery is already clearly "old" (greater than 5 years) but even then once you put a new battery in, as a replacement for a "dead" battery, you have to comprehensively check out the charging system. Diagnostic Trouble Code P0460 will result in disruption of the dashboard fuel gauge’s ability to accurately report your tank’s fuel levels. The fuel gauge readings may be erratic, or read somewhere off scale. Vehicles equipped with a low fuel warning light feature may also suffer from erratic low fuel warnings in the event of a code P0460. Unless the P0460 code has been reported alongside other trouble code, all of the vehicle’s essential systems should otherwise function normally. I would recommend that you request a check engine light diagnostic to first resolve the fault causing the P0460 code to set. The check gas cap light warning light could be due a faulty gas cap and/or small leaks in the EVAP system.

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.

Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?
ANSWER : Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the wires to the oil pressure sensor and make sure that they are connected and not broken. If everything looks good, then the oil pressure sensor may have failed. Plus, check the computer for codes and see what is stored. This will lead you to the part that could have failed. I recommend replacing the oil pressure sensor then checking to see if the lights will go out. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with the warning lights that came on.