Honda civic Cylinder misfire and flashing check engine p0303 

This actually helped me figure out it was the coil pack I could unplug that one and nothing would happen the rest when I unplugged or disconnected a little bit the car would try to turn off

Yup straight to the point thank u for watching

Thanks for video my car having the same issue 2012 Honda Civic lx, can it also drain your battery as well.?

You welcome!!!

@@RBTheMechanic I replace the coil pack and spark plugs but still have misfired what I’m gonna do.

@@d3mb3 switch the coil to diffrent cylinder see if the misfire changes to that cylinder double check the gap of ur spark plug

Welll it’s similar but stall might be other issues

Use socket keep sticking in out clean socket over and over till u get as much as it can be possable then use tissue stick it down last of all remove the plug clean it out well

Did I check compresson on cylinder 4

@@RBTheMechanic I dont have a tester yet but plan to do that next

Swap the plugs also u never know and check the spark plug gap. After that u need to check injector and coil Paula’s and compressor for engine

Scan the check engine for codes and if u got misfire code fix that cylinder change plugs and coil is a start

Not sure injectors don’t go bad just like that I would check all basics first biggest issue is head gasket and head resurface

@@RBTheMechanic ok appreciate it man, thanks for the reply.

Check ur oil also I seen oil dirty bad wrong viscosity and immediately on start up it will do that

@@RBTheMechanic I just put a new base pan an new oil on it so can’t be the oil

@@EhMaac oh ok did u use correct viscosity

@@RBTheMechanic yes

I’m thinking it’s the coils an a small valve gasket leak that’s the one thing I can think of

Well the stall need to be figured out anyways when dose it stall when u come to red light or stop sign? What is ur idle rpm once the car is cold. I would do throttle cleaning service to get this repair started

Change the coil pack

@@RBTheMechanic my mechanic is putting new spark plugs in. I need to change the coil pack to?

@@savvyguy4180 most likely it’s the coil pack

Flashing check engine is heavy misfire so do this change out the coil and plugs

I put brand new coil packs and sparks plugs in my 09 civic about two months ago and two days ago the check engine light came on..the sparks plugs are not gapped though I don’t know if that matters..and my cold air intake is dirty beyond belief

@@kiellieferickson5506 check the gap and why is the intake dirty?

Exactly my problem right now

Well did u check ur oil level?

Well which gasket did he say? Oil in spark plug would cause misfire

Didn’t replace Coil on cylinder 3

What year make model?

Ru asking me or telling me?

No this might not be related to starter change but did u get check engine?

@@RBTheMechanic thank you for replying. I haven’t yet. But I will today. Thanks again. 👍👍

@@RBTheMechanic ok, so yeah it’s ignition coiled #4 that’s failing. But now that I removed it the tip of the gasket stayed in there. Any ideas how to get it out? Thanks.

Ok u have code for crank sensor I would replace that and see where that goes and take the car and test drive it update me

@@RBTheMechanic thank you sir I will update you

@@RBTheMechanicso I haven’t changed the sensor but I unplugged it and took it for a test drive since I heard it’s sort of the same thing and nothing changed in fact it ran rougher. Should I still change it? On a side note I don’t know if this adds to it but it smells like something is burning but I’m no professional so I couldn’t tell you what but it smells bad

@@stronknoob3084 I would replace it

From what ur saying u have bad head gasket

@@RBTheMechanic thank you for your reply. Yes I think most likely the problem. Is that an easy or something doable at home? Let’s for diyers like me. Do I replace just the gasket or what else should I do? In case I try myself.

@@ricardosom7766 first I’m not sure if that is the issue I’m only saying from what u stated and It’s not somthing u can do home

@@RBTheMechanic hi my fiend here I got an update and I thank you for your time in advance. Today I took the “terminal” I think they’re called those that go over or on the spark plugs. The kind of T form one. They’re dry, but they have a gas/water or gas/alcohol smell. The engine oil is clean, it has no sign of water in it or the milky looking. Hope you get a picture of what I’m saying. Is it normal to have the gas or gas with water smell in the plugs location ? It kind of smells like when you mix hand sanitizer with water.

@@ricardosom7766 well I understand what u mean but problem like this hard to state 100% some time it’s tiny amount and nothing will mix some times it’s only combustion pressure being pushed

Scan the car for all moduel

Did you find out what it was? Mine is the same :(

Hook up ur scan tool and scan for codes and check live misfire data on cold start up

Did check engine compresson also check injector

This could be vaccum leak highly possability bad egr.

@@RBTheMechanic is there a way to test it? We have no way anywhere now and we live on the country.

Neither i bought a new egr and put it on. Yesterday the obd reader gave me 14 codes. Today it gave me 4 codes of po300, po301, Po302 and po306. That's a huge difference. I'm wondering now if I should change the idle air control. What do you think? Again thank you my friend, God bless...

@@RogerPaul-planetx-nibiru u can take it off and block the ports with ship I use to do that

I found out has a idle speed control that I cannot clean but I can replace. Today I put on the egr and took off the throttle body and cleaned it. It got up to 6 or 700 rpm where it was on like 4 or 500 so that's a small improvement on that. I'm thinking I might ruin some sea foam through the throttle body and see what hairball at this point. I'm also thinking I might have gotten some bad plugs or or coils from the auto parts but not sure. I'm also gonna see if I can clean the catalytic converter. I'm thinking it might be clogged enough from all the carbon because i did get quite a bit of soot from the tailpipe. What do you think? I thank you much for taking time to reply brother, God bless...

Which cylinder is misfiring? What brand spark plugs u put it. Get me the misfire code

@@RBTheMechanic P0301 P0302 P0300 Ngk spark plugs

@@heaxysauxe6536 u got random misfire did u put scan tool on to see live data to see if it is misfiring

@@RBTheMechanicPlease poster come and respond to this. I’m trying to figure out similar problem too.

U have to clean it up very well and then know this if there’s oil then the gasket is no good u need to replace the gasket

What was the issue before doing all this

The issue before it was shaking rough idoland it just was like losing power. So, then I did a lot of research here and there and I changed like I said all the stuff I changed, so I got to the injectors and I thought that's the last thing I probably gotta do and yes, when I took him out they were really corroded and so and that's all. I did. I took out the injectors, put them back the way they said didn't touch this or that and? Pretty much that was it.I just can't figure it out

Did u reset the light?

@@RBTheMechanic I changed both O2 sensors previosly and the light went off. When the guy checked my car for codes before "Inspection", while Check Engine Light was still off, it came up on his monitor that more than one code, 2 codes I beleive. So he told me it wasn't ready yet and I should drive around more before bringing it back for inspection. Unfortunately, the Check Engine Light came back on and I took it to Autozone and tested it and the P0303 code came on. ONLY that code. This leaves me to beleive that this issue is fresh. I just added K-Seal in hopes of catching this problem before it gets too big. The Head Gasket being the suspect. I'll kn0w tomorrow when I test drive it.

@@Justjack613 that cylinder 3 misfire maybe the codes he got was memory codes

@@RBTheMechanic I disconnected the neg battery cable for a couple of days in hopes to clear any code. I'll reconnect on Monday and when the Check Engine light is off, I'll take it for a test ride and then check for more codes. I cannot see or find any reason for the code. So I'm hoping this will do it.

@@RBTheMechanic I'm not sure I understand what a "memory code" is.

Check ur oil level? And see if it’s clean as well? It could be oil since these engines change timing with oil pressure

@@RBTheMechanic Amsoil full synthetic every 5000 miles. I was thinking probably fuel injector, but I am averaging 41.2 miles per gallon highway at 80 mph in Utah. What else do you think it could be?

@@aayonazizi747 vaccum leak?

I’ll check it out. Thank you sir.

That’s misfire cylinder one replace coil and spark plug also these new civic have issue with injectors. Flashing light is heavy misfire

@@RBTheMechanic thank you i change all 4 spark plugs and new ignition coils now its running good its a 2002 honda civic ex

@@franciscomexico7131 nice job!!!!

@@franciscomexico7131You are lucky. I have same check-light flashing issue. I have changed plugs but yet to change coils. Still flashing so I want to go back and change possibly all coils.

Start with doing basics change out plugs and coil and reset the light also do oil change use good oil the vtec works off oil dirty old and low oil can cause this type of issue

Is it odd that the issue starts with misfire in P0302 and P0303 and I fix that issue and it comes back at P0303 and I address that issue and a few weeks later it now comes back in P0301,P0302, P0303...Oil was changed in May of this year and the coil packs were replaced earlier this year and not because I had issues at that time, I just thought it be good to change them when I was doing a tune up this past spring... I noticed this latest issue last night when I started the car up I seen the engine light flash a few times with a low vibration, and it stopped and the engine smoothed out when I drove off to head home. It only acts like that at start up..

Well mostikely it’s bad coil if u got misfire

Check vaccum leaks

It'll have P0300 Random multiple misfires...Usually needs plugs and or the piston rings are worn letting oil past the them to foul the plugs..Crank shaft or camshaft sensor..Distributor,coil or related parts if not coil on plug like newer engines..Water running down in where coils are from bad weatherstripping along the cowl or rear of hood...Usually a certain car will have a certain problem when the P0300

Did u try using gas peddle to keep it alive? It might be idle issue clean throttle is a start

That’s misfire do tune up swap the coil from cylinder 3 to another cylinder see if the misfire changes to diffrent cylinder. These cars are known from ba do hector and seals causing misfire

@@RBTheMechanic i have a 2001 eclipse rs 16 valve 4 cylinder thats what im about to do now but say if its not that what could it be?

@@RBTheMechanic I have same issue code ps301 Cylinder 1 misfire. Swapped coil from cylinder 2 to cylinder 1 and the same code po301 remains. Do I need to change spark plugs?

Did u check or change oil some time it’s caused by oil bad also moniter misfire with scan tool

@@RBTheMechanic no but I was gonna change it today.. because I was reading that yesterday

@@jeremybell5745 ok

Spark plug?

@@ashveensharma5468 could be plugs coils injector or somthing else

Did I scan for codes also look in to memory codes flashing light means misfire also check ur oil level

@@RBTheMechanicmy oil is good but it still stalls when I try to accelerate?

@@im2nyccodm500 what is ur rpm maybe cleaning throttle will help

U have to reset the light it wount turn it self off use scan tool to reset it

I did but then I drove about 10 miles and the check engine light came back on. still code P0304

I changed the ignition coil for engine number 3. It still shows code P0304

The machine runs very well and does not vibrate

@@suongle5290 po304 is misfire cylinder 4 not 3

Scan the car for codes

Did u check to see the EGR valve

Will a bad egr throw a code? How do I check it? Thanks

@@mikejames8133 some will some wount well u can watch my egr valve videos cleaning it out. Or tap on it some time it start work work and function by impact or replace it It could be leaking vaccum

Ok thanks RB, I’ll purchase a new one to be sure. I appreciate your quick response.

RB, are you a fan of Seafoam, I’m tempted to want to try it, I can’t help but feel it’s a fuel related problem.

Check the plug and check compression in engine and check injector for performance

I don’t think it’s the pump is it still showing misfire or u feel misfire shake

@RBTheMechanic missfire 3// 4 cylinders could it be my oxygen sensor showing code p219E

Thnk you for the info boss have a gud Sunday

@@tatuado5875 welcome

@@tatuado5875 I have had that oxygen sensor being the issue upstream sensor

U need to change the valve gasket

@@RBTheMechanic thank you

That’s a misfire scan the car for codes

Radon misfire and all cylinders misfire can be cause by vaccum leak or oxygen sensor can cause this I would try cleaning on upstream sensor also. EGR valve if it got one. And I’d ur oil grade and oil clean?

Please did you fix it. Please if you do, I want to know how because I’m having the exact problem.

No she friend she use my shop it’s cool

What????

This flashing means serious misfire what codes did u get?

@@RBTheMechanic I want to go back and scan it. Can oil result to misfire too? Because I saw you mentioned checking oil in some comments. But they said my oil is still alright though.

@@TamImBlessed yes inside the spark plug bore if there’s oil it will misfire

@@RBTheMechanic I just did scanning and it appears that one of my injector nozzles was bad. It showed P0304. I got it replaced. Cleared the error code, Drove it for like 20km but it did not flash check light throughout the testing process . My check light has been off totally. Normally it used to stay still even though nothing is wrong since my catalyst is not present. But after they removed the battery head, the checklight totally went off. It has not gotten back which is giving me some anxiety.

But later in the day after I finished washing my car, I decided to start the engine to check if there is any more misfire. As I started the car, the check engine light came back stable without flashing which my car has always been even without any problems. But a misfire sound came up before it settled after steaming for some seconds. It bothered me so I borrowed a scanner and checked again. It showed the same P0304. Which is pointing to the same cylinder. When you wipe an error code, does it really fix the problem or it just hides it for some moments? Because after wiping it during the day, everything was fine just that my check light was off totally, which was suspicious. Even though my car is alright, it normally displays my check engine light without flashing but steady. Which means it is working fine but there is no catalyst. But whenever the check light is totally off it usually comes up with something later. So should I just keep on wiping the error codes to hide the problem or change the injector nozzle on that cylinder again? Because I used an old injector nozzle which was in my boot. Maybe it was bad too which I’m not sure of.