How To Diagnose A Misfire on an E46 BMW 3-Series DIY

This procedure would apply to any vehicle with a coil on plug type ignition system.
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This video is for entertainment purposes only. 50sKid assumes no liability for any repairs or modifications performed by the viewer as a result of the information contained in this video.

[@OldeTimeFavorites55]

Man, you really need to pick up an E46 M3 and do all the repair and maintenance on that. You would be a legend.

[@trebeezzyy8831]

Fact

[@DaisyLucy327]

Thank You. I think you do a great job explaining how to troubleshoot the misfires. I have learned from you to perform these tests to try to pinpoint the bad part. Nobody want to buy and change parts unnessarily. So THank You so much for sharing your knowledge. I appreciate you. Saving me tons of $$$. Plus. My 2003 BMW with just over 200k miles wants to make it to 300k.

[@mikek1187]

Good troubleshooting. However, you could have saved yourself time by stepping back and thinking "what is the constant between each cylinder as you change coils?" The spark plugs are that constant. Each coil relies on plugs gapped at a specific measurement, but if there are breaks inside the plug itself, it will likely make the coil work harder to complete the spark circuit. It is certainly not unheard of new plugs to be defective. But, lesson learned: moving coils and the problem doesn't travel...check the plugs. Thank you for all of your videos, and thank you for not omitting setbacks that a lot of other repair videos tend to do.

[@bradpyron8928]

It’s absolutely the ultimate useful video among hundreds of other videos I have watched in the past week after my car start miss firing. Thank you you so much for the details.

[@stepawa]

I could watch your videos all day. Very informative and easy to understand and follow .. thanks 50sKid :)

[@SqueakyCricket]

I was at "spark plugs" 1/4 of the way in, but this was a good and informative video on how to track down a problem. You were very methodical and thorough, just don't overlook the little stuff. You can never go wrong with a fresh set of plugs, fuel filter, air filter, and then chase the big ones. Thumbs up!

[@dongkyukim3580]

these diagnosing thought process videos are way better than DIY!! thank you!

[@joeloh6572]

this video is way too awesome!!! wow i admire your passion and patience and effort!!! much thanks!

[@robby_4877]

Gotta say that I really enjoy these E46 videos. They're really informative and will help immensely with working on my E46. Thanks a lot and keep up the great work.

[@5riverz456]

Robby Palmer exactly! Jason's channel is like my go to spot whenever i cant figure out anything on the e46. Most of the times im here just for fun n to gain some knowledge about the car.

[@Ghryst]

im sick of him talking about all e46's as if theyre the same thing. although its not dangerous in this case, its almost deliberate sabotage in other videos. i wonder how many e46 owners have gone looking for a vanos or worried about breaking a timing belt on his advice, just to find out thier e46s dont have one? does he even realise that some e46's have glowplugs and not sparkplugs? is he negligent or ignorant? e46 = well over a dozen different types of engines. e46 = describes the body, not the engine, and he is talking about the engine, not the body. that certainly explains his disclaimer "This video is for entertainment purposes only"

[@immanuelwallace7095]

You all probably dont give a shit but does anybody know of a way to log back into an instagram account? I was dumb forgot my login password. I appreciate any tricks you can offer me!

[@jamesroland3629]

@Immanuel Wallace Instablaster =)

[@immanuelwallace7095]

@James Roland Thanks for your reply. I got to the site thru google and im waiting for the hacking stuff now. Seems to take quite some time so I will reply here later with my results.

[@PUMAS1313]

Thanks for taking the time to share very vital info with us..... much appreciated...

[@bmwfreeq]

Thank you for your efforts and details. It sure help out a lot when your looking for answers. Thumps up for an educational video. Keep up the good work...

[@forcedtosignup2]

Thanks for this. I had a misfire vexing me for months. I wound up following these steps and sure enough, a plug swap made the misfire move. New plugs and it runs great! Sadly, this was after I took it to a mechanic who had replaced the plugs. They had only about 10 miles on them but one was bad.

[@pitufo0gomez607]

YOU ARE AMAZING! I had a misfire this morning before going to work, i looked up a video and u saved my life i fixed it right away! Great job and keep it going! Thank you

[@powerplay8355]

So errrr, what was the issue and solution?

[@HeterosexuaI]

​​@@powerplay8355 for misfires you could do what 50s kid did and check over everything, or just check the things that are easiest to fix first. check your spark plugs, check your coils. both of those are basically plug and play parts. if it's neither of those, everything else is a bit more of a pain in the ass to deal with and you should probably come back to his channel to figure out what to do from there. personally, i don't like to bother with the more complicated shit like compression testing if i don't need to. not that compression testing is hard, it's just that i know if it's a compression issue I'm just gonna be way more pissed about it.

[@VincentMMoore0]

Thanks for all your documentation and videos!

[@kompuiheartsu]

Thank you so much for these videos, you give so much important information and give me hope I can fix my car by myself! Pls don’t stop making videos!!

[@tstruthe]

Thank you 50sKid this was very informational. Awsome video. Subbed!

[@onewontdo]

This video is doing me tons of good right now with my M3. Had solid orange engine light on, very rough idle with tons of shakes. Time to change the coil #4!

[@taylor9255]

Mine just started doing this out the blue today ! Drove to work fine , then started it up to go home and was running very rough until fully warm !

[@Yamakado]

This is just an incredible information video! Awesome job, thanks a lot for sharing this!

[@scottdillon1]

Thanks for sharing your knowledge, great video

[@5riverz456]

what obd2 app and dongle setup are you using in this video? i have an e46 and i was looking into getting some scanner specific for bmw so i get specific codes. i got elm327 w/scanmaster elm, INPA, BMW Logger, peake reader and some generic scanners. just dont like the idea of carrying my laptop plus there is no room in the car when im using it and i have to translate the codes or look up the definitions for peake reader and my generic scanner. what would you recommend as a decent scanner for e46 e39 n such?

[@nicholasvonrhine6311]

The importance of the spark.great video.

[@allansrensen2141]

I agree with the others. Excellent videos, clearly understood and professionally recorded.

[@repcsi]

Thanks for vid, interesting and good as always! :) For an initial approach and if the engine is cold sometimes I check the coils with an IR thermometer if they are in the same range (and I'm lazy :) ).

[@MrNightmare1971]

50'skid, I had a misfire on cyl 2 and your video helped me out, I did switch the coil packs to see if the fault followed, and it didn't, but only watching you video did it occur tome to check the plug as they were new a few months ago, not sure why number 2 went bad, but it did, and for the time being the car is running very smooth... just wanted to thank you....

[@50sKid]

Nice, glad that helped you out.

[@timothyhenry5816]

My 2000 BMW 323ci Convertible runs great with NGK 4-Prong spark plugs & Bosch ignition coils! Don't buy cheap plugs or coils. Great video!

[@timdamelio7579]

Thank you for your channel there are only 2 people on you tube i trust for DIY help and your one of them

[@dhalsim-1]

And Scotty?

[@wiredawg2005]

Thx...I think I may be running into similar issues. I have new NGK coils (2) and still getting "misfire during start" codes on those cylinders. And my NGK plugs only has 15k+ miles on them...will go install new spark plugs in those cylinders (2). And seems to start off a bit rough but once warm smooths out...at least that's what I think. And a great vid, love how you shared how things did not go as planned and needed to do additional troubleshooting.

[@ccfiberglass]

Started having misfiring issues with my 2001 Z3 yesterday. Will do this procedure tomorrow to try and fix it. Great video.

[@andrewrapson632]

Oolo

[@andrewrapson632]

O

[@janejirajurmjuree6434]

Amazing presentation to follow step by step until problem resolved... !! ways so cool

[@takingbackmejlk]

I have an older model BMW so this may not apply because of the age but I noticed you did not mention the spark plug boots. My spark plug boots or in other words the insulator/electrode in the boot are very brittle because of the age and I was checking them because it is not passing smog and as I put the boot back on the coil pack it broke with very little pressure. Just one other thing to check along with the spark plugs, they are fairly cheap to replace. Glad you fixed the issue.

[@ericlang3630]

Great video, I have an e39 I just bought. I changed the oil and then misfires started to happen. Gonna try and swap coil packs tomorrow.

[@kkwesterlund]

Thank you so much, your videos are just great! This one saved me a lot of money and trouble!

[@johnwellings3225]

very enjoyable video, tracking down the fault

[@50sKid]

thanks!

[@bryanp2780]

Thank you so much for this, I was having the identical issue as you only on cyl 1. I too was sure it was an ignition coil since I've had to replace most of them in the past 272k miles. To my very surprise the misfire didnt follow the coil swap and I ruled out sparkplugs since I had replaced mine not too long ago. Swapped plug 1 with 4 and the misfire followed, thanks bro!

[@patrickkeating2860]

loved your process. subscribed.

[@Roman-rz3qj]

Awesome and extremely informative video. Thank you as always.

[@usmcromp8769]

Thanks for you help on this one. I havent been through your channel I'm sure you say it somewhere, but that app on your phone what is that? I heard something about a bmw scanner tool is that, that?

[@drewzcutz1]

Where did u get the first batch of spark plugs?

[@ACGDesigns]

Thanks for this video! I am getting the same codes on this Touring I just got. One question though. Why didn't you try the plugs after you tried the coils, if you're doing easiest to fix to hardest?

[@TitusArsole]

I'm curious, did your coils end up being the cause of the spark plug's degradation, because i've heard of bad coils ruining new plugs?

[@ron8566]

Excellent work. Thank you. I currently have an issue in an 06’ E83 X3. It is due for plugs and I’m also going to do the coils. The symptom is what feel like misfires under acceleration. The tach jumps around in between shift points. Other thank plugs and coils, I fear this may be the transfer case gear or the chains in the

[@BihFaca11]

what website you prefer for BMW e46 spark plugs,i have a 01 330c I'm thinking about changing spark plugs. Thanks

[@bobh.3127]

Fantastic video, as always. I've got a misfire problem that I need to get around to diagnosing and this video is extremely helpful!

[@oddsteven3435]

Hey I was wondering what are the best ignition coils to purchase for your e46? When you are replacing them

[@DjDannyD19891]

Im wondering the same thing, what scanner do you have plugged into the car to get the non-generic codes onto your phone? Would be much appreciated, thanks!

[@tontonaali]

Hello 50sKid, on a E46 330ci I have all cylinders missfire code (1 to 6) and both Fuel trim banks permissible range exceeded. What are the possible causes I might look for? Vacuum leak? Thank you

[@robertotorresk7440]

thanks a lot, I found my problem(misfire) that's why I subscribe to your channel

[@bobbywarrior1434]

Great video, thanks for explaining your diagnostic method in such an easy way to understand , I would love to get that scanner app, think you said OBD Fusion ? And probably something that connects to the OBD and sends the info to the phone ? Please let us know, and again thanks for a great video

[@TheDrGoggles]

what app are you using? Love the video's my dude!

[@luisamedina1]

how do you use your cel phone with your car? Is there any app? Thanks in advance!

[@RacoonAndres]

nice video, my e46 has had all the coils swapped and new sparkplugs, still random misfires on IDLE and my RPM's are close to 600-500 hence it feels rough, I'm new to fixing cars but could the ICV or DISA be a cause of it?

[@Drenalin]

Hello, great video ! Why don't you use INPA rough test for identify which cylinder is misfiring ?

[@cemyanikk]

I did my e85 Z4 (M54B25 engine) maintenance according to your videos. Thanks a lot for helping videos. Now my car is stalling when the cold starting. I replaced the spark plugs, ccv system with the new ones.Also i have new one coil as a spare part. I can not see any codes on OBD. What is your suggestion?

[@everyangle4310]

Hey I would like to start off by saying you have some great video's. I have a 01 330ci mass air flow is suspected to be bad, my scanner said it was reading a really high quality (I forgot the number) I guess it's supposed to be around 7 ish. can you help me out with testing the MAF with a multimeter? would be a nice video if you got the time or even a link would be very appreciate it. keep up the great work.

[@0m4rpakisolja]

I have the exact same issue, I didn’t realise you had a video of this exact same issue but mine would misfire quite badly to the point the engine actually shut off, took mine to a mechanic and since he knows I diy myself he scanned the codes, confirmed it was misfires and just told me to change the plugs and bring it back for him to scan just to confirm the misfire is gone, the engines running a whole lot smoother, but still need to get it scanned as it does feel a bit rough on a cold start. (update) its having the issues again, was smooth for about a week before it had a problem firing up once more, has quite a severe bounce on the revs. scanned the car again and flared up DME activation ignition codes on all cylinders

[@maxverbeeten4483]

Nice vid, What obd connector do you use to Read codes with your phone?

[@uyenngo4170]

Hi 50sKid, I like all of your videos... My E46 went thru most of the problem that you had. Today I had P0302 (Cylinder#2 Misfire detected) and P0335 (Crankshaft Position sensor "A" circuit) at cold start... As the engine is warmed up, the misfire disappeared... I went thru engine drop test, all 6 coils were good ( I could feel the differences when dis-connected the coils) But I found cylinder #2 and #4 ignition coil were soaked with engine oil (not the other)??? I removed the spark plug of 2 and #4 , and checked....It seems normal, no sight of oil or burned. So I cleaned up, re-installed, cleared Trouble code and monitor in the next few day to see the same problem coming back or not My questions: How did oil get there? Which part do I need to replace to stop that oil leak to that area? FYI, spark plugs are 40K miles old and Head Cover gasket is about 60K miles old Thank you in advance!

[@dmcd1248]

Fully appreciate the detective work [kudos], but as mentioned long after spending days on diagnosing the coil packs, I'd suggest checking &/or replacing the spark plugs 1st. Based on years of experience, I always start w/ the easiest potential solution 1st & proceed to the more difficult & expensive causes as needed...step-by-step. FWIW; I've run into quite a few defective spark plugs (as-in; fouled, broken, shorted, cracked, arc'd etc) over the years, so, that is always worth a consideration 1st. Bosch plugs seem to work w/out fail on my Beemers.

[@narutolop]

Thanks for the videos!!!

[@kkampy4052]

Have you inspected the ignitor boots? I had an E36 that had a bad miss on takeoff but was ok once moving. Turns out I had cracks in the tips of the ignitor boots, replaced them and it ran great. I had to squeeze the tips to see the cracks.

[@joekelly9902]

Very informative video! I am missing that grey conduit wire in the third bay of the manifold. It looks like some sensor is broken off in there. what sensor is that? I don't even have the grey conduit! No engine light is on and the car runs fine now Thanks to your video!!

[@SanDoval201970]

hey have sporadic miss fire on cylinder 4 and 5, swap from cyl 1 and to to 4 and 5 coils and new plugs, still have misfire in 5 and 6 ,, do you think I should test the injectors?

[@TheNogibear]

Thank you for the step by step video. I have an error code for oxygen sensor - P0161: 02 heater circuit (bank 2, sensor 2). Is this sensor on the error code for the pre-cat sensor on this video or the one you had on another video that you replaced under the car? Thanks in advance.

[@HBOIchip]

Can you pull out a plug hook up to coil and check for spark that way to determine if a coil is bad? getting ready to help a friend troubleshoot his misfire(s).

[@BRZTrackDays]

Thank you for the thorough troubleshooting. I wonder if the problem going away when engine was at temperature is because the high temps assist on ignition. Could the gap on the spark plug not being set to spec be the reason the spark was failing even though it had only 10K miles in it?

[@agyemanbonsu6544]

I love your tutorial ,

[@MichaelJohnson-ss7qf]

Good video. Great troubleshooting skills

[@50sKid]

thanks, bud!

[@quartznation9499]

Can you or should you clean o2 sensors? I keep getting too rich codes (but im really poor)

[@Fingerboardmaster200]

I have this problem where my car sometimes cranks really long and when it happens i also get a power loss, i have tracked it down to being a cyl 3 fault, i guess the power loss comes from missing a cylinder. I bought a new coil pack and the plugs were changed at the beginning of the year. I'm gonna replace cyl 3 plug and see if it helps

[@ynebogatov]

I got a question/puzzle for you. I realize this isn't a support forum, but decided to give it a shot on the off-chance that you decide to reply. I recently used your video guides (which are excellent btw) to perform a whole lot of maintenance/repair on my 325i. Starter, CCV, oil filter housing gasket, most of the cooling system, most pulleys/rollers, belts, various hoses and gaskets that I had access to ... A pretty substantial overhaul by my standards. The problem I have now (and it could very easily NOT be related to the maintenance at all) is that I'm consistently seeing a misfire (enough to set a code and deactivate the injector) on cylinder 3, when the engine is cold. At that point I can feel the car running on 5 cylinders, vibration and loss of power are very pronounced. Once it's warmed up, I can restart the engine and the misfire disappears. Everything is working perfectly otherwise. What I've done so far: - swapped injectors - no change (cylinder 3) - fuel trims - slightly positive, but less than 5% - compression : 160-170 in all cylinders, - ** have not done leakdown test yet, no air tools ** - I havent moved spark plugs around, but they have less than 20K on them, I swapped them when I changed the valve cover gasket 2 years ago - I moved coils around, no effect - seems all are in good order Can you recommend any further diagnostics/debugging I should do? I'm a little out of ideas. I thought the compression test would give me a hint, but cylinder 3 actually has higher compression than most others (168). Any advice/help would be appreciated. Thanks,

[@50sKid]

Swap the plugs dude--that's what you haven't done. Don't rule them out just because they are less than 2 years old. Mine were also about 2 years old and look what my problem turned out to be.

[@ynebogatov]

Thanks for the reply, will give that a shot tonight.

[@ynebogatov]

You were right! I guess the best explanation is often the simplest one :) Can;t tell from its appearance that anything is actually wrong with it, gaps seem the same as on others, no oil or any unusual residue on it really, but swapping it with cylinder 4's plug made cylinder 4 misfire. Mystery solved? I hope so.

[@kevinVersus]

After replacing my dead alternator on my 325 it ran rough and idle drops too 500rpm after giving it a light rev. I check coil packs, replaced spark plugs and vcg too. Still runs like crap. Checked maf too..

[@winslowleach1835]

Nice shirt. Thanks for all the help.

[@sueipaz]

@50skid I have the same problem at cold start, the idle is rough. I changed the spark plugs and still same issue I did what u did by unplugging the coil connector but the car was already warm, it also happens at a complete stop, I have E60 N52 2007, the has me frustrated not know what it is.

[@daavisst3630]

i have the same problem, but it starts when engine warms up. do you think it could be the sparkplugs also?

[@stonesthrow420]

My 2005 325-CI is doing the exact same thing. Rough idle only on cold start. My code reader says Cylinder #2 misfire, then is says random misfires. Then goes away after warm up. Im gonna try this power balance test soon. The plugs are all new...I installed the exact plugs you recommended

[@arnolduk123]

The quickest test is pulling each coil to find the problem cylinder(s) misfire but it does not rule out a dodgy injector that could be leaking and wetting the plug(s) which clears after the engine is primed. I got a 330i E46 with a multiple mifires on 2 or more cylinders which has now got to the point of causing the engine to not start and idle too low on a cold start. Engine is fine at very high revs and changing the plugs with new one clears the misfires temporally and then the misfires are back again. I'm thinking injector(s) are the cause.

[@And-War]

HI 50skid, im getting P1352 & P1345 but I have only had these pop up twice while I left the car sit for over two weeks, after 15 mins the engine light turns off and the car starts to run smoothly again. I noticed it on start up, as my car is shaking more than its used to, Thing is I changed the Spark plugs myself but coil packs are orginal.

[@e39exclusiveclubpanama33]

Good afternoon 50s kid,I bought a 2000 BMW 523i with a m52tu (Latin America market) the car I used it fine until a day one hose broke off, and when I started the car, noticed backfires on intake manifold, replace the MAF sensor with a cheap one since I couldn't find a bremi or a Siemens one, replaced oxygen sensor after that car began smoking during start-up thru one of your videos we came to the conclusion that it was the CVV did the replacement and when I started the car car began loosing oil pressure, when I opened it noticed that car had a nasty oil sludge problem, cleaned it out and took it for a drive, had idle and under load issues , in which lead to misfiring replaced the intake manifold gasket idle when cold is fine, but when car gets hot under load it is rough and when I stop idle is bad but if I turn it off and back on car idle is fine again, what would you recommend to do, I don't have a scanner for my car,y car it is not obdii it is obd1 with the round connector

[@4jup4ter4]

Interesting. Accelerating last week and mines felt like it was loosing pressure, then the RPM needle jumped up normally to shift. CEL came on throwing a P1304 code. After restarting, it was running just fine and CEL light went away. Today on the freeway trying to pass a car, from third gear the RPM fell down from and acceleration felt like it was choking on air. I need to do these test tomorrow morning. Thank you!!

[@degiri231]

What app do you use on your phone? How does it work? Thanks @50kids.

[@christiannavas684]

Really awesome video

[@ericmatheri9394]

Very educative, am having same problem, my mech will check all this and i'll revert

[@ChefO301]

Does it have anything to do with cross threading your spark plus when putting them in? Asking because I feel like I did that in my 6 and getting random misfires as well while it’s cold

[@damien1999]

I’ve got the following codes on my 01 330ci it’s starting to get a little frustrating I recently had the cam sensor replaced and ever since then it’ll at times change sound (it gets much deeper) and power is reduced its almost like something’s stuck in the exhaust pipe, I shut the car off and restart it right away and it’s gone. any ideas? P0300 Random/multiple cylinder misfire detected P1192 *** Post-catalyst fuel trim system bank 1 P0155 o2 sensor heater circuit (Bank sensor 1) P1447 EVAP control system purge flow monitoring P1351 Ignition coil control circuit high voltage P1353 Misfire cylinder 6 with fuel cut off P1349 Misfire cylinder 4 with fuel cut off

[@ramazkutateladze538]

I`m having such a problem with misfires on my X5.. I think the bad fuel is guilty in this case.. however, I`ve had a serious misfire about a year and a half ago and I changed spark plugs with denso irridium IK20TT spark plugs. Have done about 25000KM with them.. bought them for a reason that those were the most durable spark plugs with a decent amount of igniting power.. hmm.. however, through it`s lifetime I doubt my car has ever had injectors replaced or cleaned.. so could you please tell me the size of injectors an M54B30 uses from the factory ? and sometimes I get fuel trim errors when obd scanning my car on cold

[@voltesfive928]

when are you make video replacing cylinder head? I'm waiting

[@ryedubs1789]

Hey Fifty. I have a P1347 code - Manufacturer Control Ignition System or Misfire. It sounds like clunking, stalling, and a loud muffler. Sort of a chugging noise. Or thumping noise. Any ideas?

[@joel7465]

Can someone tell me if I can carry out the same test (listening to the to the engine drop) on a 4 cylinder? the wiring on the leads are a little more exposed than this so dont want to be disconnecting them if there going to give me a surprise! thanks

[@evantugby]

Excellent video.

[@TheAlfaDrive]

Hello #50skid ive an issue with my e46 325ci (euro manual 6speed) it has a misfire only after the first time that the fan starts runns fine when cold, when you restart it it drives fine... so i checked the coils i start the engine untill it start misfire the i will search for the nonworking one i change it while the engine is running and nothing changed... spark plugs changed with iridium ones new same issue the only way to drive it is to unplug the MAF sensor the ecu starts to delever a lot of gas and the fixs the issue but i still notice a low performance under 3000 rpm after that its rocket. I will try to find coils and test them out but i think i will have the same issue.

[@matsmalling]

Recently went to take a look at an 04 330 started the car up let it run for a few minutes then began to hear a faint knocking sound, few minutes later, check engine popped on. Car has 150,000km on it and shifts smooth everything else seems fine but I'm not sure if that knocking and check engine light is a misfire

[@benjigreenlee9540]

What would you think of cylinder 1 2 & 3 misfire, no cats, no downstream O2 sensors and no sap

[@samer4977]

what is this diagnose mobile app and device i wanna buy one like this for my honda 93???

[@TheDaikashido]

what do those electrical harnesses look like on the inside, are they green?

[@gabrielgomez2747]

where did you purchased the first batch of spark plugs?

[@robertmcglinchey3347]

On my 325ix very similar behavior. Any idea why the plug? Someone commented copper is better than platinum.

[@ameen6473]

My 2003 E46 325i is straight piped i have been driving it for over 1 year never took her out in the snow but i did it once last week and started misfiring and when i checked it said cylinder 4 misfire and i have changed all the spark plugs and.checked all the coils they are working do u have any idea what that could be now its just cranking wont start at all

[@eduki]

Lambda sensor maybe... What's the software/OBD combo you're using? I use the BMWScanner but it's a pain in the ass since my laptop updated itself (yes, itself hahaha) to W10

[@50sKid]

kzbin.info/www/bejne/jZ2xmnhsj9R6rM0

[@tehhbenouu]

Hey! i need some help, my 330i m54b30 keeps getting a really bad misfire if i stay idle for a while, for example at a red light for too long, then its only firing on 5 cylinders, if i delete the codes its fine, i removed the spark plugs which looked fine, but the rubber connectors had cracks right through every single one, and i replaced those, the problem is still there, i ordered new spark plugs today even tho i replaced them a year ago. any ideas?