M54B22 no power and misfire on cylinders 1-3 on high rpm

[Mumar]

Hi!

I've got problem with my 2004 E46 with M54B22 engine. For some time now my car has low power and absolutely no power at high rpms - more than 5500 rpm, after that rpm car accelerates very rough and slowly. If I hold it at high rpm for few seconds it throws misfire error (Burning fail cylinder ...) on some of 1-3 cylinders. It isn't always one of them, it looks random sometimes it is just one of them, sometimes there are two. After that car enters safe mode which switches off after I turn the car off and on again. There are no other errors. The same happens at lower rpm about 4000rpm if I drive at constant speed of about 150km/h or more on highway.

I've seen in adaptation values that there is very different multiplicative value between banks. On bank 1 it is -12, and on bank 2 it is +9.

I tried switching coils and spark plugs between cylinders. I also replaced fuel filter and fuel pump. I also changed DISA unit for new one because old one didn't work. About a year ago I replaced CCV and valve seals with cylinder head rebuild. About half year ago I replaced vanos seals because of thrown code. Nothing of this changed anything apart from that now there is only this burning fail error.

I recently changed lambda sensor and the one for bank 1 was all white - lean condition when sensor for bank 2 was black/grey which for me looks ok.

The car oil consumption is quite big - 1l per 1000km but still has good compression - about 13,5 bar which is the same at every cylinder.

Any suggestions will be welcome,
Marcin.

[MarcoZandrini]

Hmmmm. When I started reading your post I was thinking "fuel pump and filter." But, I see you replaced both. Question is what brands of pump and filter did you install? Hopefully the pump is made by Siemens/VDO, and the filter is made by either Mahle or Keyser.

it sounds like a fuel delivery issue. An easy way to determine if it's the problem is to check the fuel pressure. Item #2 in the link is the cap for the pressure test valve. The pressure has to be at least 50psi at all engine speeds.

http://www.realoem.com/bmw/enUS/show...diagId=13_0900

[Mumar]

I've replaced fuel pump with Bosch unit and fuel filter made by Mahle. I've checked fuel pressure and it stays at 50psi. The problem is that I'm able to check it with pressure gauge only when vehicle is stationary.
Maybe one of injectors on cylinders 1-3 is leaking and DME is cutting fuel dose for this cylinder bank, is that possible? Do you know if I can confirm that somehow using INPA?

[randy72877]

Negative fuel trim on bank 1 and positive on bank 2. Could be a leaking injector. Remove the fuel rail from the intake and turn the key on to prime the fuel system. Check the tips for leakage/dripping. I'm not sure if your car has two catalytic converters or one (325's were the lowest model sold here) but if it has two (one on each bank) and one is restricted or clogged you can get the symptoms you have. You can test back pressure at the pre cat o2 sensor holes.

Sent from my SAMSUNG-SM-G870A using Tapatalk

[blarf]

Additional vacuum leaks? Smoke test.

Are the oxygen sensors hooked up properly? There may be a diagnostic test you can run, or you can just disconnect (engine off) one of the sensors, run the engine and see what the computer says (error codes, lambda values, etc).

Leaky fuel injector? Maybe. Hook up a fuel pressure gauge. Engine off, ignition on. You should see ~3.5 bar (IIRC). Turn the ignition off. The pressure shouldn't drop quickly.

[MarcoZandrini]

I doubt the problem is vacuum leaks. Why? As the engine speed increases the air entering the engine via vacuum leaks decreases as a percentage of the total air entering the engine.

What are are the specific codes? What are you using to scan the computer for codes?

[flyfishvt]

I doubt it's vacuum leaks only because a vacuum leak would affect both banks equally. My first thought when I read this is you swapped an o2 sensor. As stated above you may have 2 precat sensors. If you do it's possible you reversed the connectors for bank 1 and bank 2 sensors.

[MarcoZandrini]

I think swapping the pre-cat sensors would cause issues but I'm not sure swapping post-cat sensors matters too much.

[Mumar]

Hi All,
Sorry for late reply. I didn't swap pre-cat sensors between banks but replaced them with new ones and I'm sure that I plugged them correctly. The car had fuel trims like that before changing lambda sensors and I doubt they were previously inserted incorrectly because a year ago when I bought this car it was running fine and I didn't touch the sensors until now.
I gave up my diagnostics and left car at the mechanic. Apparently either I measured compression incorrectly or something happened after that because right now it is: 14-14-14-7,5-11,5-12,5 (bar) I'm going to double check it myself and if it's true I will probably be looking at engine swap.