Anyone here a BMW tech?

[achi]

Hi,

I am looking for some help and input is most certainly appreciated. I do not know where else to turn in my city.

I have been chasing down a misfire issue with my 2003 320i (M54) for about a year and half. Been to the BMW dealership. Took my $ couldn't diagnose and fix the problem. Another shop could not identify it either. Both German vehicle specialists.

Upon start up has a misfire #2 cyl, if cold weather misfire is really bad. If you shut car off and retart, no misfire. It has been a while since I read cleared the codes to get a new read. It is not a faulty plug or coil.

I have the codes recorded earlier but cannot get a proper repair to take care of the issue. Been a while so I will have to dig them up.

Any help would be appreciated.

Thanks in advance.

Cheers,
Achi

[David Williamson]

Not a BMW tech but I have owned them for years and done some work on them, nobody else is helping so here goes a few ideas. I would expect they tried this already but .... Have you tried switching injectors to see if the issue moves with the injector? Could be leaking and flooding a cylinder when cold? Also I had a coil that was intermittent, miss-fire on first start and good on the second start after running a couple of minutes. Swap coils and try it, after that it's got to be a physical issue in the engine, time and $$ to go looking and it could be many things. We have 2 '07 335i with the twin turbo M54 engines.
David W

[Desert Cobra]

If you have established that it is #2 then change out the injector, plug, coil pack. Check ground on coil pack. With #2 plug out bore scope it. Check compression #2. Depending on miles could be carbon build up on back side of valves. Fuel injection has a choke mode at cold start and an idle valve below the intake manifold. That may be sticking. Clean or replace. Not sure about 320i. I have a 2004 330, 6 speed. Try BMW CCA forums.

[achi]

Thanks for taking the time to provide me your feedback.

I fixed the DISA valve (it had rounded itself and was not functioning as it should, it was flapping uncontrollably), I replaced the flap and ensured it moved as it should.
I have swapped spark plugs and it always returns at #2, so I swapped the coils, again #2. When i brought it to the dealership to check, they said they did a test on the injectors, coils, and plugs. Said they took them out and did a leak down (i could be wrong on the term) test on them and they were good. Upon closer inspection, after a bit of time, I took the plastic cover off the top of the engine to realize that the screws that hold the injectors, looked like they were never touched. So there is probably an issue. I will be taking the injectors out to swap as that was one thing I had not done to date. I will check the ground on the #2 coil pack. All the air hoses are good and there are no leaks, and the CCV under the intake was working fine, but I cleaned it anyways. If your there, you may as well do it.

I have read countless threads of what it could be based on the codes I had before. I don't think I saw the BMW CCA,Thanks!! The list of possibilities to correct was endless and mostly the issue was resolved with a swap of the coil or new plug, or a hose with a hole but my issue seems to go beyond that.
I do not mind spending the time to look out for issues, but this car, (this is the first and last BMW) seems to be so complicated in its engineering. Yes, I guess you pay for that... :)

I really enjoy driving this car, so I am trying my damnedest to try to fix the issue. Again it is way more prominent in the cooler months (here it can go to -30C in the winter, but will happen more readily when the temps in spring or closer to winter).

I will test the codes this weekend and get to the injector and check the compression.

All told, this is what the dealership charged me for, and as it appears, they did not do the work for which I paid.

Thanks again, I really appreciate you guys taking the time to help me out.

Cheers,
Achi

[JimLev]

Achi,
I’m not a BMW tech by trade however Ive been wrenching on my 540/6 and friends BMW’s for the last 20 years.
Do you have INPA? It is a software program you install on your computer. It will enable you to look at and control almost everything in the car.
There are newer software programs available too. I use INPA.
It will give you more info than a generic code reader.

If you only have a hand held code reader post your Pxxxx codes.
As the others have said it could be anything.
Have you had a smoke test done to the engine? That will find vacuum leaks that you will never see.
It could be an intake manifold gasket.
How many miles are on the car?
Do you have a maintenance history of what has been changed since new? Specifically parts under the hood?


One of the best BMW forums For the E39 chassis is:
https://www.bimmerforums.com/forum/forumdisplay.php?202-1996-2003-(E39)

If you want to post a question you’ll need to register, it’s very easy.
You’ll find me there, same screen name as here.

OOPS, just noticed you said ‘03 320, that’s an E46 chassis but same M54 engine as used in the E39, just smaller.
That forum is here, however you’ll find more info and help on the E39 forum.
https://www.bimmerforums.com/forum/forumdisplay.php?15-1999-2006-(E46)

Here’s another link that you can look at all the parts and part numbers.
The prices shown are usually wrong as the dealers have really increased prices over the last 4+ years.
https://www.realoem.com/bmw/enUS/partgrp?id=EV13-USA-03-2003-E46-BMW-320i

Have you looked at o-ring #6 here?
https://www.realoem.com/bmw/enUS/showparts?id=EV13-USA-03-2003-E46-BMW-320i&diagId=11_2879

Most misfires are either coil, injector, plug, oil in the plug well, or a vacuum leak.
Seeing it’s only on cyl 2 that rules out a lot of items common to all 6 cylinders.

Regards,
JimLev

[achi]

Hi JimLev,

Thank you for all that info. I will apologize up front if this reply is all over the place.

I forgot to mention above that the dealership also said they performed a smoke test, and nothing. Again, I have may reservations as to whether or not they really did the items for which I was invoiced. To late to do anything about it.

I have been to the forums, again thank you for putting them back in my short term memory. Thank you for putting the links in the reply in case I had not been aware they existed.

I order my parts from a place in CT that offers lifetime warranties, so I am always referring to realoem site to confirm part numbers as US did not get the 320i. I do not have INPA, will look into that.

Many thanks for all this information!!!! I now have a few more items to check..

Car has 200,000 kms (120k miles), hoses under hood are flexible so I assume they are not brittle and old. Also has the cold air hoses installed under the intake. Not certain if these were / are aftermarket. I may have a valve cover gasket leak, not sure this would cause issues, but you never know. I recently changed the fuel pump, it died a very slow death. The misfire issue predates the fuel pump replacement.

Cheers,
Achi

[JimLev]

FCP Euro is probably one of the best places for parts, lifetime warranty is a plus.
A leaking valve cover gasket will let air which will screw with the short and long term O2 sensor trims.

[Desert Cobra]

Sounds like you are taking all the right steps to track down the problem. Things that happen only during warm up or at cold temps are the hardest to track down. What about gas quality? During winter here they put in alcohol. This causes my BMW with re-programmed EMC to ping. Same on the track if fuel is poor. Pump may say its 91 octane but it may not be. Try a few full tanks of another brand of gas. Also high mileage cars may have carbon build up which raises compression, which requires higher octane. This mostly happens under load ie, when you are at mid rpm's and try to accelerate. Anyway it doesn't cost much to try.

[JimLev]

Also try a few bottles of Chevron Techron, good stuff.

[gpeppin]

Hi,

I am looking for some help and input is most certainly appreciated. I do not know where else to turn in my city.

I have been chasing down a misfire issue with my 2003 320i (M54) for about a year and half. Been to the BMW dealership. Took my $ couldn't diagnose and fix the problem. Another shop could not identify it either. Both German vehicle specialists.

Upon start up has a misfire #2 cyl, if cold weather misfire is really bad. If you shut car off and retart, no misfire. It has been a while since I read cleared the codes to get a new read. It is not a faulty plug or coil.

I have the codes recorded earlier but cannot get a proper repair to take care of the issue. Been a while so I will have to dig them up.

Any help would be appreciated.

Thanks in advance.

Cheers,
Achi

Change the plugs.....all of them

[achi]

Thanks so much, I will add a few additional details.

When I got the car, I brought it to the dealer for inspection, dealer told me to use regular unleaded, big mistake. After a year, I noticed some sluggish behaviour. Spoke with someone who owned a car like this (he is also a tech, I met later) and said he put nothing but mid or premium, so I switched to prem Costco gas from regular unleaded, I put a bottle of bmw techron in when I made the switch but have not added another since. Costco gas never goes stale here and it is a top tier gas.

I figured when I said lifetime warranty, you would figure where I get my parts. I was about to place an order for parts when the border shut down. I am kind of stuck now with parts as parts cost so much more here. I live close to the border and can go get them without using a freightforwarder, but if parts ship across they are subject to so much extra costs. An example oil here is $15/ litre, + filter & taxes in $175 for oil change if I do it myself. From FCP oil and filter $55. Even with exchange its a no brainer.
I will continue with the diagnosing, I was ready to order a new gasket to start when everything shut down.

I looked up the INPA, is there one you recommend, there were more than a few different ones.

Has anyone ever used Seafoam, I have heard good things but afraid to try in this car.

Thanks everyone.

Cheers,
Achi

[JimLev]

I bought mine on eBay from some guy in Romania. Some of INPA is in German, but pretty easy to figure out.
You also need the correct cable to go from the car to the computer.
Here’s more info.
https://www.bimmerforums.com/forum/forumdisplay.php?233-Diagnostic-Software

Never used seafoam.
I get Techron at the auto parts store, get the concentrated one.

[Desert Cobra]

Some fuel additives are mostly cleaners. If it is an octane problem you may need an octane booster additive, not just a cleaner. I use them when I track my car. It delays the onset of pinging which is handled by the computer by retarding timing.I have not found the Costco Techron additive to do much to octane problems. Owners manual and sticker on gas door should say " Unleaded gasoline premium only Minimum octane 91". That is for a new car. Again more miles more carbon build up. More build up more compression. More compression more octane. Race fuel is 93 octane. Aviation fuel even higher. A boat racer on a high altitude lake will use aviation fuel.