So basically there are about 50 things that can cause a misfire. Got it. I think I've found around 48 of them, so a hearty thank you for saving me the trouble of finding the last two. : /

Awesome video, quick and concise yet completely and utterly informative. About to attack the vacuum leaks on mine, cheers!

This is one your best videos on e46, thanks!

My E39 520i (M54B22) has now 425 000 km and runs smoother than ever, mostly on LPG btw. One issue with these engines which is VERY often overlooked and therefore rarely mentioned: 🤓 On the M54 and M52, the hydraulic lifters OFTEN clog due to heat and cause all kinds of engine issues and fault codes, incl. misfires (!) but NONE of these codes actually mention to check the hydraulic lifters - they always "blame" another part. Hence you end up replacing alot of parts which might still be good without getting to the root cause. Try HYDRAULIC LIFTER CLEANING FLUID first, this stuff is meant to do just that, and it often really works! This is the simplest fix for your M54 and M52 engine, and you can't really hurt the engine with cleaner lifters, even if there is another fault as well. Think of it as Vitamins for your engine! And please: Try it first, comment and thank me later 😉

This was very helpful, I'm going to do the valve cover gasket and then go after the sensors on mine.

Love the raw data dump vids.

Nathan you got that e46 looking sharp

Awesome video mate, I’m building a e46 at the moment as well!! Brilliant cars!!! 👌

Excellent video. Wish more auto DIYs were like this, explaining what could cause the fault and why it happens as well. Thank you.

"Gonna be stankin" Yes, yes indeed. Love your channel!

I have a 2002 BMW e39 M54 525i M-Sport and was having ongoing problems with misfires and fuel trim issues. Every mechanic I saw said the cause was probably an air leak. Nothing definitive was coming up on the code reader. After 2 smoke tests and a compression test, these are all the parts I ended up replacing to fix it : the cylinder head (rocker) cover, all ignition coils and spark plugs, air filter, air intake boot, tube elbow, MAF sensor, DISA valve, PCV valve, idle control valve, all the oxygen sensors, fuel pump, fuel filter, fuel pressure regulator and it was still misfiring. Eventually I figured it out.... The cause of the misfiring was clogged Catalytic Converters. Now replaced and the car is running like new. Not a single 'specialist' mechanic I saw ever suggested the misfiring could have been caused by the cats. I hope this helps someone.

Thank you sir . Very easy to understand very knowledgeable i never subscribe to anything but I subscribed to you very impressive

I had a bad ignition coil causing misfire, replaced and now runs perfect

Hey nathan, what do you think about hella for the sensor? Is it good?

Best videos Nathan- Dave

Thanks Nathan awesome video

Will a bad maf sensor cause lean bank codes and misfire codes ? I’ve got all them at once all vacs seem good gonna try order a new maf but was just curious on that with the miss fire codes

Thanks Nathan! Could expand to the issues with the throttle position sensors in these cars? Thanks

Hi. I have high fuel trims at idle, rough idle in the morning. I made smoke test and smoke was coming out from this round thing at the back of DISA, can this small thing make +20% at idle? Thanks

I have e39 with the m54b30, one day on the Highway I was driving about 60-70mph and went mid throttle and the rpm began bounce between 3-4K. Shortly after once I got off went from 1500-4K with out a problem but right after my check engine light came on and the car wouldnt rev past 2K. I haven’t gotten the chance to scan the code but could it be the coil packs ?

Hey Nathan, I am wondering if a bad gas cap would cause low pressure and possible misfiring?. Another great video! Thanks for all of the help over the years!

Lol, just got done fixing lean codes and misfires on all 6 cylinders on my 2001 X5. After throwing plugs, coils and O2 sensors at it, I took it in to get smoked, and they found vacuum plug leaks and some bad hoses as well. The DISA had broken too, and was about to dump its metal axle into the intake! And to confirm your statements, it is a 158k mile M54, but it's been having intermittent CELs for at least 3 or 4 thousand miles. Clearing them got me through for a while, until the vacuum leaks got so bad that it would go out of fuel trim range in minutes.

Hi Nathan, it’s a pleasure watching your videos. I’m having a common issue that’s has been all over the e46 forums, which is a low idle in drive and reverse. It’s to the point where the red oil light flickers sometimes when the rpm dips far enough. Would you say that is due to a vacuum leak even tho the car has no codes? Car runs great other than the low idle. Has 135k and I plan on going over maintenance. I already replaced the hard coolant lines, ccv, oil pan gasket and oil filter housing gasket.

Does the throttle body ever tend to go bad having a eml light issue right now

What would cause p1343, p1351, p1345 misfire with low fuel. I replaced a couple days ago fuel injectors, sparks and coil, Brad new disavale and cleaned the ICV AND YES THAT WORK REALLY WELL... so how am I still having these codes.. BTW the car is sitting I don't drive it cus it'll stall out after being on for a bit sometimes it'll stall out after a couple seconds, remember the old disconnect the coil connector and if the engine acts up then the coil is good? Yeah I did that and I noticed cylinder 1,2 and 5 aren't working but how if those coils are good and sparks. I had them all sent out to get tested and their all working. So it's not the coils or sparks... maybe it's the coil harness connectors?

i have a question is thier ways to upgrade those parts on the n54 engine to alleviate the problems with it

I have an 04 Bmw 530i with the m54, I haven’t started it in a couple weeks bc of a situation but I did a tune up with plugs and coils and replaced the battery, now when I went to start it the whole motor was shaking really bad and misfire nasty, what do u think this could be caused from

How are you sir great video. I got 2003 325ci . It’s in limp mode code p1634,p1635 car running rough and no throttle any help Would be great thanks in advance

would you recommend buying an aluminium disa rebuild kit for a "while im there" kinda upgrade or buy a brand new one?

What headlights do you have?

Brake boosters or servos DO go bad on E46's. I've had one fail on an E46 compact. I've had both hoses deteriorated on my 328i the splits were both out of sight at the bottom. Smoke test is definitely something to consider if you think you've a misfire due to a lean situation.

ive seen so many of your videos, you are great. if i unplug the maf it purrs plugged in its stumbling. does the default running mode it goes into w unplugged maf bypass anything besides maf for it to run

Love it

What about cylinder 3 misfire and I had a check engine light for exhaust valve I did change the sensors for the exhaust valve but it still running rough I believe I have a low compression on cylinder 3 which I believe might be because of the valves the exhaustive valves has a problem

Thank you bro, my car always misfire 1 and i will chek it all

Did you have some e46 Transmission video? Mine is 323ci wont go fordard and reverse it’s like always in neutral sometimes goes reverse or forward but late and couple seconds after acceletating

Hi, my e46, is boggin down everytime i press the gas. Only goes up to 2000rpm and boggs out. No power. It red P1145 reffering to solenoid valve running looses control curcuit. Is that the vanos solenoid. Because when i searched for solenoid valve. It comes up the vanos solenoid. Is it the vanos?

What about misfire with the AC on at highway speeds & when you turn the car back on it’s perfect

Hard to start and shaking, it was 2 bad fuel injectors for me. I’m a do it yourself guy and this about drove me nuts till I solved it. ( pull spark plug wire and see which cylinders have the problem)

So basically everything on the car causes a miss fire. Christ. Spend $1,500 and find out it needs a spark plug.

shot in the dark but maybe someone can help been having random misfire and hard start for a while and it ONLY got better when i disconnected the rear 02 sensor. replaced the usual. plugs, coils, smoke test, cam sensor, fuel filter and checked for leaks. what can it be?

So I Have 2001 Bmw E38 740il that had timing chain guide failure so I stopped driving since I didn’t have the funds to fix it but wanted to get to it but never did. I now plan to get it fix but now it won’t start. What would you advice if its been seating for 2 years that still has half a tank of premium fuel but doesn’t want to start like it chokes. No check engine light has new battery but now car won’t turn on whats my next move from here any advice or list what I should do.

I replaced my spark plugs and got rid of my lean codes and i replaced my valve gasket. But i still have a misfire in my 1 3 5 6 cylinders. And i also got 3rd cylinder misfire with fuel cutoff

my car has codes on misfire all cylinder, and idle rough. what should I change first

Need your help with my 325i 02 bmw

I could use a little help with getting my e46 figured out. 04 325i 5spd. Started out throwing eml light under any kind of heavy throttle. Figured vac leak so we placed all the lines, pcv, ccv. Problem still there. We stepped it up and changed out the intake manifold, throttle body and disa all from a good parts car. Intake boots have been replaced as well as the maf sensor. Issue still there. Very odd thing when the maf sensor is unplugged the car runs great and doesn’t throw any eml code. Tuned ms45 ecu. Sap deleted catless headers with o2 sensor delete. Any suggestions or ideas what to do next?? Thanks for reading.

Hey Nathan, Love your channel. Hey trying to figure it out issue with my 04 e46 330ci with issues stalling right after it warms up(10 minutes). Right after that I try to start it and it goes into Limp Mode. I changed MAF, new Intake boots, spark plugs, intake/exhaust camshaft sensors, TB, Cleaned ICA, DISA o-ring and refurbished. After it goes into limp mode it shows following codes: 2772 tank valve activation, 2796 throttle adaptation values incorrect, 5E19 CAN Data fault from DME.

Hi man what’s your thoughts on removing the mechanical fan and replacing it with an electric fan?

PLEASE HELP I got PO174, PO420, PO491, PO492. Then decided to clear the codes while car was running. Got scared by the sound and switched the engine off. After the starting it again it stalled almost immediately and now it idles on about 500 rpm and the car shakes. What should i do?

I have the 2001 bmw 330ci 5 speed manual P1341, P1343 and P1351 (cylinder 1,2 and 5 misfire with fuel cut off) I replaced the fuel injectors, spark plugs and ignition coils along with the ignition coil harness wiring, fuel pump, exhaust camshaft sensor, intake camshaft sensor, crankshaft sensor, mass air flow sensor, lower and upper intake boot, disa valve, both up stream exhaust oxygen sensors, cleaned the ICV... Fixed the vacuum hoses that were in the back and one that comnects below into a little air tank, i replaced the hose thats also connected to the F on the upper intake boot... Only thing i haven't got to yet is the catalytic converter 02 sensors and i have those just not installed.. please help. Misfire is so bad its terrible. And i can smell it too... Is it oossible my cat or cats are clogged? Hard to start up the whole engine is bogging... And moving cus the misfire is so bad

update on the cats?

Still getting a misfire even though all of these are fine. Check pressure on cylinders as well. replaced plugs and coils twice. Nothing. At low RPM’s it’s fine but as soon as i go above 4500rpm it misfires on cylinder 5

If you own one of these cars long enough and you have any mechanical ability, you’ll know this engine compartment like the back of your hand.

Hopefully someone can get back and solve my problem’s. 2003 330i having times where while sitting at a light car will get thrown into limp mode. A bit of a rough idle and black smoke upon start. Have to clear the code at times to be able to drive the car. Any ideas…??

I was told it might be my disavalve on my e46(330xi) but I get a nasty idle sometimes and then either we’ll idling or sitting at a light the car will randomly start miss firing and either chug too much air and not enough gas or too much gas, I have to turn the car off and on and then it’s fine…any opinions?

I have a 2001 bmw 330i that starts easily and drives smooth as butter but idles somewhat rough. im gonna watch this video when I get home from work

My car is not drivable it starts and then dies shortly after. I cleared the codes but now cannot get them back not sure what to do. Maybe a maf or cam/exhaust sensor?

My 1999 528i m54 drops idle while its warming up, once it warms up its runs perfectly. What could it be?

Im super stumped. Rough idle SOMETIMES. When it's rough idle, 80% of the times it progresses to dropping cylinder 6. I changed so many parts. I won't list them all. But the symptom continues.

P1083 how do I fix?

Where is the map sensor?

What about the idle control valve? would that cause a misfire?

My car runs fine in open loop/ maf unplugged. But with it plugged in it falls on its face and throws advanced intake timing codes

BMW E46 318i 2004 Car start but rough idle diagnostic show vvt error code

P0505 code ?

why not start the car to show us whats the sound and symptoms when is vacum leak…

There were of course 4 cylinder models...

28A2 code

Bro said 525xi lol u did for get

FIRST!!!! Lol

You should record in a 16:9 aspect ratio. This isn't good for an informative video since it's so cropped.

5 series is NOT E46 - those are 3 series.

How are you sir great video. I got 2003 325ci . It’s in limp mode code p1634,p1635 car running rough and no throttle any help Would be great thanks in advance