Help 2008 bmw 328i with misfires on 1,2,3 cyl and power loss

[Tigre77]

HI ALL
I have a 2008 328 automatic with 99,000miles the car starts up but a little shaky after engine worms up #1,2,3 shut down and start misfiring only runs on three cylinders,i swap the coils no change,i swap the injectors no change,new sparkplugs no change.
If I drive it only goes at 20mpr and then starts shaking like crazy engine light flashing very violent shaking goes into limp mode I scanned and got cylinders 1,2,3 misfire with fuel cut off,bank 1 o2 senser code,multiple misfires,eccentric shaft plausibility,no power,engine feels restricted.
so I replace the eccentric shaft sensor with no luck,new sparkplugs,a compression test I got 150 across but I believe its suppose to be 200 but cheap gauges so I guess 150 it should still run ok.
me and my neighbor spent 7ahours one night testing everything and we notice the bank2 cat was glowing red so we though that the cats were clogged so I detach the cats from the engine and see if it would run better but no change it still misfires and runs like crap.
I removed the valve cover to check the timing but everything lines up and didn't see anything bad or not normal and also my sparkplugs are black I guess from the engine running too lean.
also clean the MAF sensor because on my scanner on data stream it is showing some crazy readings 1789 lbs/h ,vanos intake adapt -1.5deg,vanos exhaust -2.2deg which looks not normal?
on inpa I shows voltage control module internal temp !74.96
voltage engine temp !22.68
voltage coolant temperature radiator output !105.48
so also some issue with engine cooling? I know my water pump is working and my thermostat is open when it should and fans come on when the dme tells it to and cools the engine and the normal running temp is running on idle is 109-111f and then fas come on and it gets cooler.
so I'm stuck I don't know what else to try,maybe its a timing issue or cooling issue or ecu is bad which I pulled out and open it and had my neighbor who is a computer ingineer test the resisters and its working fine he didn't see anything wrong with it.
any help will be appreciated thanks

[jclausen]

We had a car e90 that was running like crap, found out the ground wires were either loose or the aluminum bolt that held them down was broken and could not,be tightened on the valve cover

[Tigre77]

I’ll look into that today thankyou

[bmwdirtracer]

I'm going with jclausen's idea, because there really aren't too many things which affect one bank only; certainly the coil ground is the most likely I can think of. (Do NOT OVERTIGHTEN any of these tiny nuts. Snug is tight....tight is broke. (Yes, I know the word is "broken";poetic license)

Um, plugs running lean are light tan or white. Rich or oil fouled plugs are black, just for future reference. But it's no good trying to read plugs by color, when you've got 1 bank misfiring.

Now, the bank 2 cat glowing red is very concerning. You have serious mixture issues on BOTH banks.

What, exactly, are you using to read the codes? Can it read BMW specific codes? Because, for instance, a BMW specific scan tool will read codes like "O2 sensors are swapped", while a generic OBD reader will not. And, um, this would cause all your conditions.....but only if someone's done some work which might have caused swapped sensor leads.

Tell us what you're using to read the codes.....

It's really easy to swap those plugs, if you don't know. Did you have the valvecover off lately?

Oh....you did.....if you have a good scan tool, and it reads live data, try diconnecting one bank's front sensor, and then seeing which one disappears from live data. If the wrong one goes away.....

[Tigre77]

yes its running rich I ment they are all black fouled plugs and I'm using inpa and a otc scanner for my live data,i shot a video of the live data from inpa but I I'm trying to figure out how to load it on here.
I already had the valve cover off twice once to install the eccentric shaft and another to check timing so maybe I did swap them ill check on that thanks.
yesterday I let the car run for a while to see if I can get any other codes to pop up but got same codes 1,2,3 misfiring and pre cat bank 1 codes so I notice that when I put the car in reverse or drive the engine starts to make laud kinda banging sound and shakes even more violently then when its on park,so I disconnected the maf sensor and when the engine is on drive or reverse the noise goes away and accelerates smoothly but when I drive it I will not go past first gear it only stays in first gear sooo I'm thinking the maf meter could be bad and also when I look at live data the air mass is at !700 so I unplug it and no change so maybe the maf is bad?

[Tigre77]

ok so today I checked to see that the o2 bank1 and bank2 were not swaped but also had a spare o2 sensor that my neighbor gave me a couple of months back so I swaped it with the bank1 o2 sensor and turn the car on and the idle was really smooth and I didn't get any error codes,that was a huge change from how it was idling before.
so I took it for a test drive and right when it went into second gear the engine ligh came on again canner showed 1,2,3 misfires but now o2 sensor code,so I thinking the bank1 cat is maybe clogged up no good and also on the test drive the car had no power.
so turned it off unplugged the maf again and it actually switch gears this time and ran a lot smoother.
I think the problem is the cat on bank1? goin to see if I can do a back pressure test next.
or maybe the maf is also bad?
I do have a spare bank1 cat in my garage my neighbor gave me also,should I change it?

[MarcoZandrini]

Unplugging the MAF causes the ecu to run an overly rich fuel/air mix. That tells me that there could be vacuum leak or the MAF is kaput. Can you monitor the MAF’s signal? It should be showing about 4 grams/second at idle.

[Tigre77]

On my otc genesis is showing 4635 lbs/h what ever that means I don’t know so I hooked the scanner to my friends 330i and the maf was at 45 lbs/h.
on inpa maf pressure is around 23 %

[Tigre77]

My air mass is 18kg/h on idle

[bmwdirtracer]

Eh....I'd be looking at things which affect one bank.

However, I would absolutely NOT recommend all the work of swapping the cat/manifold for bank 1, when you haven't tested for backpressure, and have nothing really pointing at a bad cat. I'm not saying the cat is good;; I'm just saying that there are quite a few things which are more likely culprits right now. If you remove the bank 1 pre-cat O2 sensor from the header, and put a pressure sensor in that hole, rev the engine to ~3500 rpm, and the pressure sensor shows less than 2 psi, a clogged bank 1 cat is not the problem. (This test takes maybe 20 minutes. Swapping that cat will take quite a few hours, much swearing. Your choice.)

[Tigre77]

Well like I said before I swapped the o2 sensor on bank1 pre cat and the code went away and idles really normal with no check engine light,but once I start driving get to second gear lights flashing cylinders 1,2,3 misfires engine runs rough

[Tigre77]

Another reason I suspect the bank1 cat is because at normal temperature the bank1 cat reads 160c before cat and 150c after the cat with a temperature gun.
the bank 2 is 260 before cat and around 180 after which I think is not hot enough.

[Tigre77]

Would anyone know where I can hookup a vacuum gauge to on the n52?

[bmwdirtracer]

If you're talking about measuring the backpressure, you use a pressure/vacuum gauge with a silicone hose, attached to a fitting screwed into the O2 sensor ports, at the primary O2 sensor holes, and then the secondaries, after the cats. You should not see more than 1.5 psi, maybe 2 psi, when revving to ~3000 rpm or more.

If only the primaries show excess pressure, the cats are clogged. If the secondaries show similar excess pressure, the insides of the cats are likely now in the mufflers, clogging them.

[Tigre77]

I want to hookup a vacuum gauge to it that way I can get more than exhaust readings, I don’t see any vacuum hoses on the intake manifold after the throttle

[Tigre77]

Hello so after work I removed the bank1 o2 sensor from the cat turn engine on and had no rough idle engine felt so smooth.
put it in reverse and drive still smooth and took it for a drive in the neighborhood wow I could not believe it no more misfires and had power!!!!
im goin to remove the bank1 cat with the one my buddy gave me which I took it from his trash he was throwing out because he said had a bad o2 sensor and he had spare ones anyways.
also goin to replace the bank1 o2sensor with a new one hopefully the bank 2 is all ok....anything else I should change or look for?

[bmwdirtracer]

All that's good, and I believe it's very likely you've found your culprit......BUT:

(1) Well, if a catalyst dies, it's because something killed it. Putting a new cat on without fixing the issue is very, um, wasteful of a good cat/ If, for instance, you have excess, or inadequate fuel, or oil dumping into that bank is still missing a bunch of power, and, well, you didn't fix the causative issue, Think about what that means.
2) If you throw the cat at it, and spend all those hours doing that swap, you still will never know for sure that you did the right thing. Sure, the better performance with O2 out is very indicative...but there's nothing like having numbers to prove why...

Sure, if you do that, replace the engine mounts, and the gaskets you disturb, and if your car wasn't always from Kissimmee, maybe a broken exhaust stud or two.

If the cat's dead, you should replace the primary O2 sensor on that bank.

If bank 1 cat is clogged, it's extremely likely that bank 2's will be, too.

We don't have codes for this?

Tell me that you've had a BMW specific diagnostic computer read all the codes.....

[Tigre77]

That’s right I don’t know the history of this car and I suspect that cat on bank 2 is goin out or maybe not 100%,I’m glad that it runs wayyy better but I don’t know why the cat is bad and that’s what I’m worried about.
only way to find out is to put in the other cat and a new o2 sensor and drive it.
only other issue I see on inpa is ....cooling temperature output!!!!reading crazy voltage but engines cooling system working as it should

[Tigre77]

IMG_E0832.jpgIMG_E0832.jpgIMG_E0832.jpgIMG_E0832.jpg

[bmwdirtracer]

Seriously? 105 volts on the coolant temp sensor???

Abel, or dworthy, help me out here - I do not use INPA....WTF is this saying? Even if I can't see a decimal point, 105 volts makes no sense at all??

[Tigre77]

That’s what I’m thinking wtf I don’t understand that, so I hooked it up to by neighbors 330i and it was normal readings so I don’t understand

[Tigre77]

Ok so I replaced the bank1 cat and it was bad,put the spare one and the car runs a lot better we it runs now and idles great.
took it on a drive but still feels kinda sluggish on takeoff almost home and check engine light came on cly 1,2,3 misfire,I ordered the bank1 o2sensor should be here soon and hopefully that will fix it.

[bmwdirtracer]

See post 17.

[Tigre77]

We’ will see what happens when the new o2sensor bank1 one comes in I guess i also ordered an exhaust pressure tester

[bmwdirtracer]

You need to worry about why the DME thinks the coolant temp sensor has 105 volts. I'd suggest that you unplug the radiator outlet temp sensor, and see what INPA says the voltage is then.