P0304 Explained - Cylinder 4 Misfire (Simple Fix) 

But is one that literally just covers the duh answer what google would say. Pretty poor video in terms of not including a lot of different things that could and do trigger p0304

Excellent! Glad it could help!

That makes our day to hear, James! Thank you so much for the kind words and subscribing. 😊🙌

Glad you like them! Thanks for watching.

Happy to help!

Happy to help, Gabe 😊 Happy and safe driving!

So glad we could help give you peace of mind, Kali!

No Problem!

Shit I wish it would fixd mine

Coil pack

Did it? I think it would, you must have the answer by now

Have you got the issue fix ? If not are you still driving it

Did you get it figured out? Fuel injectors can be fairly straight forward to replace.

@@Sheevness somewhat irony ce light comes and goes now sadly

You probably have more serious problems in engine. Swap it

I got the same problem, do you already fix it?

Check number 4 plug

Spark Plug and Coil Check.

What was the problem

Depends on your make and model. Google "(your car make and model) firing order" to find out which cylinder is C4

how can you tell the difference?

@@chuckpotts458 a coil pack is basically a "box" of all coils in one, with normal small plug wires going to the plugs. If you swap the wires themselves you'll change the firing order. The animation here, shows the individual coils that sit literally on top of the spark plug. Then small gauge clips plug into them. As long as you keep the clip/cable in the same spot, you can move the coils around to see if one is bad.

Ive been doing it for years. Its simple. 1:un bolt coil pack 2:un plug the 'sus' coil pack 3:repeat 1&2 on a different coil pack 4:switch them, plug them in bolt them down. And re scan, if the 'sus' coil pack carries the code to the other cylander then it is the coil pack. If not then it is most likely the spark plug. If one plug is bad replace it and see if code clears. BE SURE to check for oil on the plug. If there is, you should replace valve cover gasket, and seals. " Recommend replace all spark plugs if you can" You can also remove the coil pack and use a multi meter to test the resistance, if you have one and know how to use it.

@@All_praise4Allah you are explaining correctly for a "coil on plug" type. I mentioned coil packs, I should have said ignition coil pack or ignition block to be proper. You cannot move the packs in those types. If you switch spark plug wires around it will be big trouble.

@@Steve-og3cr i know how to seperate the wires

Ugh I feel you. What was the issue

@@gabrielavega91 the FI hose was kinked. However Im back to square 1, because its back hard starting, and sometimes it doesnt start at all. Im thinking the brand new spider is defective

​@@bigcartoonyIIV did you ever get it sorted??

@@KishBish Yea it was the distributor cap, and a bad fuel injector. Now my battery is dead and on a flat..lol Im 2 steps from retiring that truck..lol

Good point! Thanks!

Yes O’Reilly just quoted me for one $75

Rip

Jack up radiator cap drive new car underneath install cap. Jk.

Did you ever fixed the problem? I changed spark plugs, coils, and fuel injectors. Code still appears.

How did it go? What was the problem?

It's cylinder #4, but anyway it's the same even if it's the firing order. Firing order is expressed something like 1-4-3-2. No one thinks of that as "cylinder 2 is the fourth to fire."

Many other causes..injector could be dirty

You should be proud...i don't even know how many stars was mine....ja!

Me too did everything have a 5.3 vortec

Have you fixed it yet ?

No my next guess is to try a running compression test.

Did you ever fix your problem because I’m having the same problem and I tried everything

@@leeadams9004 I just sold the stupid car lmao

Your o2 sensors read how much fuel is been burned so if they are failed mean ur computer is dumping fuel into it and reducing it drastically on points wich can lead to engine failure

@@arielzambada9911 yes but my question is could the bad o2 sensors be causing the misfire noone ever states this in videos if bad o2 sensors can cause engine stalling/ rough idle

Yes

Yeah idk about that. But my honda odyssey has 6 injectors and they are $40 each though.

Yes.

No. A misfire is a serious problem and will cause the car to run rough. You need to get it fixed right away and don't drive the car with a misfire. You should have it towed to a service center and fixed. Typically a car with a misfire has a large loss of power, so you don't want to drive that anyway. A misfire is throwing, at least a little, unburnt fuel through your catalytic converter, damaging it, and you don't want that.

@@TheLarryBrown my 2008 Honda accord EX-L V6 sedan Looks like the previous owner has installed as installed a spark plug with epoxy. My car started running rough and now it is throwing the P0304 cylinder for miss fire code. I'm pretty sure I just need to change all the plugs and quarterpacks but the spark plugs are oil fouled and and I guess autozone suggests I replace the mass air flow sensor too

@@freedompioneer4311 Spark plugs fouled with oil indicates some serious problem, are you sure about that? To see 6 spark plugs fouled with oil seems extremely unexpected. If it's just the top of the plugs, the part with the white insulator, then you may have a leaky valve cover gasket, a relatively minor problem and easy fix. If it's the actual plug, the bottom part that sits inside the cylinder, then you're sucking oil into the intake manifold and the car would be smoking like a mofo, possibly through a blown EGR valve...my Beemers can do that. If you are getting oil into the intake, replacing plugs and wires and mass airflow sensor is going to do little/no good and the plugs will just get fouled again. Anyway, everyone always suspects the mass airflow sensor but there are plenty of other places you can get problems. If you are going to change the plugs, do that first and see if your problems go away before doing the mass airflow. Anyway if you are only showing a misfire on #4 that does not lend suspicion to the mass air flow nor any problems outside of cylinder four. If you aere only getting misfire on #4, trade the plugs and wires and ignition coil between #4 and some other cylinder and you may see the misfire follow those #4 components. If you put the #4 plug on #3 and then #3 continues to work ok, you know that plug is ok. Finally, in the spirit of "test, don't guess," try to test the mass airflow sensor and observe faulty behavior before you just needlessly buy a new one.

I've been driving a hyundai elantra 2009 car with p304 code for a few months without any issue. I've sent it to workshop a few times but they couldn't figure out what's wrong. They've did the swapping method and the same p304 still happened. They suspect it's the ecu but the technician who repaired my ecu said otherwise.

I’m getting that code , and the exhaust is in a bit of rough shape. That’s something I should check out your saying ?

Fuck cylinder 5. We're talking about Cylinder 4. Why does EVERYTHING have to be about Cylinder 5 with you?

Lmao 🤣 🤣 🤣 🤣

@@EmeraldView HAHA!

Depends where the vacuum leak is at. My mustang had both lean and rich

I have the same issue. Audi A4, p0304, new spark plugs in all four, 4 new coil packs, 4 new fuel injectors, only about a week later and the check engine misfire came back on.

Did you solve the problem? My is250 cylinder 4 is missfiring. Coil and sparkplug not the issue

So today we found out that somebody put coke in our gas tank. Fuel injector wouldn’t open up, our mechanic found sugar.

@@cecigalvez630 wow. What jerks. Can anything be done?

@@cecigalvez630 Did you sleep with someones man ? Lmao. Why would anyone do that .

Same with my Toyota. But then again, BMWs and Mercedes can cost $400 just to change the oil.

Honda has to take Ngk plugs. Around $15-20 each. I have an odyssey so I need 6. However the coils are $40 each.

Or, educate yourself about what the cause of the issue might be, and try replacing some parts yourself before taking it somewhere and spending a ton of money on a shop repair.

@@DSquire10 riiiight... OR you could do some actual diagnostics by doing various tests to determine what the problem actually is. Rather than just blindly throwing money and parts at it like 95% of people out there.

@@FreshAsFxck bro let me know how to diagnostically check my car I get the same code

Is the problem solved?

@@batuza4117 yes... problem solve....if it wasn't....it would of been replacing the coil pack, them MAF sensor

I had all my spark plugs switched out, after p0304 code. A week later check engine popped back up, called mechanic they said it might just be cold out, i dunno

Did it work or was it just cold

​@MJ.401 same code on a 2022 vehicle with 80k miles I drive spirited changed spark plugs went away 2 weeks later cylinder 4 was misfiring might clean out coils before I buy new ones hopefully that helps.

lol i literally paused it there to hit the comments

I think he doesn't really know alot

I had to replay too... lol

Kevin Robinson same here lol

Yes. V4 engines do exist. Not as common as inline 4 cylinder engines. So the LOL is on you. Haha