P0303 Code: Cylinder 3 Misfire - Causes and Troubleshooting Guide

so today I'm talking about a p0303 code what it is and how you go about fixing it and so what is a p0303 code well it's a cylinder 3 misfire detected and what does this mean well basically each cylinder inside of the engine needs to have air going into it and gas going into it and at the right time there's a spark plug that sends out a spark which is going to cause a small explosion called combustion that's going to send the Piston down which is going to turn the crank and is going to keep the whole engine running but when you get a misfire code the combustion is not happening or it's happening sometimes and not other times but something's going on that's causing an issue with this and so it's going to have to be troubleshooting or why and a p 0303 code is going to point to the number three cylinder if you were to have a P0301 code it would be number one a p 0302 code would be number two and so on and so on if you go Google your engine in firing order or cylinder location usually you can look at Google images and you can find the number three cylinder on your particular engine since there will be some differences on how it's located but the one the computer's seeing a problem with is going to be the number three cylinder and one thing to note about these misfire codes is that if you're only getting this P 0303 code then that's only going to point to the components that's on the number three cylinder but if you're getting multiple misfires for example if you're getting like a p 03000 code and multiple other cylinder misfires like a P0 301 or something like that then that's going to point to something that would affect the whole engine so that would be something like a bad fuel pump a bad sensor a vacuum leak or something like that and the way you go about troubleshooting that would be completely different than how you would just troubleshoot a p0303 code but if you are only getting a p0303 code and no other misfire codes then very likely it's just going to be some kind of component on that cylinder and so what would be some possible causes of a p0303 code well it could be a bad spark plug it could be a bad spark plug wire could be a bad coil could be a bad fuel injector and if you have an older vehicle with a distributor cap then it could be a bad distributor cap and so there's going to be some different ways you go about troubleshooting this code the main thing you're going to want to check for is you're going to want to check for spark on the number three cylinder and you're going to want to check and be sure that fuel is going to the number three cylinder so first thing to do is locate that number 3 cylinder on your particular vehicle there's different types of coils if you have a coil pack like this you could check the spark plug wire going to the number three cylinder be sure that it looks like it's good and that it's plugged in and things like this depending on your vehicle the year the manufacturer different things like this there is different types of coils but they all do the same thing they provide high voltage to the spark plug so that it can sent out a spark when it's needed if you have a vehicle that has ignition coils like this where there's one on each cylinder you can't swap it with another one that's good so for example you can swap it with cylinder number two and then you can start the vehicle and see if the code follows so if you got a p 0 302 code then you know that indiction coil is bad a really quick way to rule out whether or not it's a spark issue like the coil or bad spark plug wires or things like this is just to check to see if that cylinder is getting sparkk and there's some different ways to go about doing this one of the easier methods is just to use one of these inline spark tester tools and basically one side goes on the spark plug and then the other side goes through the coil and then you start up the vehicle and if it's getting sparked then you'll be able to see it inside of here you'll see the spark lighting up right here and that would quickly tell you whether or not that cylinder is getting spark these are real low cost tools usually less than like $115 I'll put a link Down Below in the description if you need to see what I'm talking about but basically if you could test that c to see if it's getting sparked and if it is getting sparked then you can move on to the fuel injector and if it's not getting sparked then you can move on to troubleshooting whether or not you got a bad coil or what's going on but the first thing to do is check and be sure that you're getting spark going to that number three cylinder if you are getting sparked to the number three cylinders there's no issues going on there the spark plugs are good things like this then the next thing that could cause this is something's going on with the fuel injector on cylinder number three and again there's some different ways to go about troubleshooting this on some Vehicles they're easy to get to so you can swap them with another one one that is working so you can swap cylinder 3 fuel injector with cylinder number two fuel injector and just see if the problem follows some Vehicles make it harder to get to so you can also test the fuel injector with the multimeter and be sure that it's working there's some good YouTube videos on how you go about doing this but the next thing to do would be to check that fuel injector and be sure that it's working and also keep in mind that the wiring going to the fuel injector if there's any kind of problems with it if there's an open a short a bad connection something like this then that's going to cause the same symptoms as a fuel injector so be sure to keep that in mind but the next thing to go and check is going to be the fuel injector and the fuel injector wiring and so that's basically it I just wanted to give a basic overview of how you go about fixing a vehicle with the p0303 code if you have anything to add please comment down below if you have any questions ask me and I'll try to answer them this video helps you please click like please click subscribe and have a good day