[Misfires] - Cylinderbank 1 keeps misfiring - Troubleshooting

[PCG.DTCH]

Hi all,

Long time ghost reader, finally have something to b*tch about and ask you guys for help :P.

Current situation:
'08 M3 E92
151k km
DCT

Mods:
- Evolve Testpipes (4 months ago)
- DCT Tune (GTS Software)
- Rear silencer mod

Maintenance parts done:
- TBA (Rebuild.co.uk - 7k km's / 5 months ago)
- Main Bearings
- NTK Pre-cat O2 sensors
- New NGK Sparkplugs (while troubleshooting this week)
- 6 months old battery


Car was running great since i've changes the TBA's.
Last saturday i was traveling to a friend, who lives 80km from me. And i was taking the M3. As i was cruising and the car warmed up, it was running super smooth.

with +- 90km/h in 7th gear, i floored it a couple of times and noticed a little bogging. Didn't think anything of it, because the lack of torque of the S65 and i had the car in manual mode.

When i turned up onto the highway, i was chasing a motorbike. He was clearly enjoying himself and the exhaust note of my M3, because we kept "playing" on the road and overtaking each other.

Speeds for the next 10 minutes where between 180km/h and 240km/h, had it multiple times around the 8000 rpm. Engine and car sounded perfect and felt great.

After playtime was over, i've put it on the cruise control with a speed of 120km/h in 7th gear. Trying to save some fuel :P

after +- 10km, the Check Engine Light(CEL) came on. And the car went into limp-mode.

BimmerLink App threw me these codes:

279F - E-Box fan control electrical diagnosis
2B37 - Misfiring with shutdown Cyl. 3
2B57 - Engine emergency program activated
2796 - Engine emergency program activated
2B5D - Vehicle speed controller release
2B36 - Misfiring with shutdown Cyl. 2
2B38 - Misfiring with shutdown Cyl. 4
2B41 - Mirfiring with shutdown several cylinders
2B43 - Combustion misfiring exhaust gas degassing Cyl. 2
2B44 - Combustion misfiring exhaust gas degassing Cyl. 3
2B45 - Combustion misfiring exhaust gas degassing Cyl. 4
2B4E - Combustion misfiring exhaust gas several cylinders

After shutting the car down, resetting the codes. they all came back immediately.

Since my M3 identified as a 316i, i limped it home on 4 cylinders. Took out a different car and went to my friend.

My initial reaction was: Sparkplugs & Coils. Since every M3 Thread with misfire issues mentioned them.

Bought new sparkplugs. (same as the ones that we're in it for +- 15.000km), switched Coils from Cylinder Bank 1 > 2 and from 2 > 1.

Deleted all the codes, started it and it threw all the same codes again.
But now, including Cylinder 1.

2B35 - Misfiring with shutdown Cyl. 1


After that, i've switched the O2 sensors around. Still no change in codes.
But since i had everything removed, i installed 2 new O2 sensors, just to be sure. (OEM NTK ones)

Cleared all the codes again, then started it again.

The car does something weird.
- On initial startup (coldstart) it sounds like all 8 cylinders are running.
- When i let it idle, the moveable Redline (in the cluster) goes back to 5500 rpm. (it doesn't throw a CEL then)
- When i let it idle a little bit longer, around 3-4 seconds, it throws the CEL and the redline drops to 4000 rpm. Then it also throws the "Reduced Engine power" warning.

After that, i deleted all the codes.
When i start the car, and keep the rev's a little above idle. And scan again for codes, it only throws 3.

2B36 - Misfiring with shutdown Cyl. 2
2B57 - Engine emergency program activated
2796 - Engine emergency program activated

When i let go of the throttle, and let bimmerlink scan again for codes (after deleting the 3 mentioned above) it throws all the original codes again.

(these, without Cyl.1)

279F - E-Box fan control electrical diagnosis
2B37 - Misfiring with shutdown Cyl. 3
2B57 - Engine emergency program activated
2796 - Engine emergency program activated
2B5D - Vehicle speed controller release
2B36 - Misfiring with shutdown Cyl. 2
2B38 - Misfiring with shutdown Cyl. 4
2B41 - Mirfiring with shutdown several cylinders
2B43 - Combustion misfiring exhaust gas degassing Cyl. 2
2B44 - Combustion misfiring exhaust gas degassing Cyl. 3
2B45 - Combustion misfiring exhaust gas degassing Cyl. 4
2B4E - Combustion misfiring exhaust gas several cylinders

Upon now, i've done the following:
- Sparkplugs changed
- Made sure Coils aren't the problem
- Switched and replaced O2 sensors (primary ones)
- Made sure the TBA's work (both open and close while running)
- Battery is 6 months old, charging is 14.2 volts.

reading upon these issues on these and other forums, i'm going to:
- check compression on all 8. (to make sure i didn't bust a valvespring)
- I've ordered new OEM exhaust gaskets (current ones are OEM BMW and installed while installing the Testpipes)

But after that, i'm clueless what to check / do.

Any help is appreciated. I'm currently clueless.

Thanks in advance!

[Redd]

Im guessing exhaust gasket. But also take off your plenum and run it without. See if the codes go away without the plenum.

[RocketyMan]

OP. Get some actual data. ISTA has a nice misfire screen that you can easily help identify misfire and the cause (good guess, or maybe a better route to go down).

Taking off the plenum will do nothing barring the intake temp sensor as this engine is a SPEED DENSITY calculated--no MAF in intake.

I would also try resetting all adaptions in the DME. I'm not sure about your tune, but it could have an effect on the running operations and the DME calculations.

[PCG.DTCH]

I've just purchased ISTA, currently on the installing side of it and when it's done. I'll make sure to test it using ISTA.

[charliev68]

I would physically inspect your valve springs on Bank 1 to see if they are broken or fatigued. I know it sucks, but you will have to remove your camshafts. It would be the final step after you have eliminated everything else. Good luck 🍀 and hope it’s something sensor related instead of valve springs.

[smokinjoe64]

Originally Posted by PCG.DTCH

Hi all,

Long time ghost reader, finally have something to b*tch about and ask you guys for help :P.

PCG.DTCH have a look...

https://www.m3post.com/forums/showpo...01&postcount=8

[RocketyMan]

Originally Posted by PCG.DTCH

I've just purchased ISTA, currently on the installing side of it and when it's done. I'll make sure to test it using ISTA.

I would get a refund. You shouldn't have to pay anything for ISTA (aside from a physical adapter--SW is easily obtainable for free).

Anyway...post some results when you get a chance.

[PCG.DTCH]

Originally Posted by RocketyMan

I would get a refund. You shouldn't have to pay anything for ISTA (aside from a physical adapter--SW is easily obtainable for free).

Anyway...post some results when you get a chance.

15,- euro's isn't a huge price to pay for a good working downloadlink with the latest ISTA.

I've searched the internet, and besides torrents, i couldn't find one link that was working.




Anyway, i went back on the chase.
After getting ISTA to work and deleting all the codes, i checked a lot of things with Ista.

- Injectors
- Sparks

And while checking the injector times, i came across the following.

After clearing all the codes, i checked the injector-timings.
On startup, all 8 injectors fired equally. (between 2.75ms and 3.60 ms on idle). No problems there.

After +- 5 seconds, Cylinder 3 cuts out. (The injector switches off)
After another 3-4 seconds, all the injectors on bank 1 switched off and it throws the CEL together with the "Reduced power" warning. (316i identity crisis there :P)

So after doing that a few times, and everytime Cylinder 3 would cut out first.
I've changed injectors (bank 1 > Bank 2. And Bank 2 > Bank 1). And again, Injector Cyl.3 left the chat eary, followed by the other 3 cylinders.

So after checking everything using ISTA, and switching all the basic stuff around, it got time for doing the compression testing.


Cylinder 1: 180 Bar (We use metric here in the Netherlands)
Cylinder 2: 179 Bar
Cylinder 3: 0.00000000000000 Bar
Cylinder 4: 179 Bar
Cylinder 5: 180 Bar
Cylinder 6: 178 Bar
Cylinder 7: 180 Bar
Cylinder 8: 180 Bar

Checked multiple cylinders twice, to make sure the readings were correct. But looks like Cylinder 3 isn't doing it's thing anymore.

Needle on the tester isn't moving at all, so that points me to believing the valve-spring is done. Or worse.

I've contacted the shop that did my bearings etc to report my findings and asked for a full diagnose of the problem and repair.

Hopefully it's just the spring, and not something major that requires a new motor. But i'll report that back when the car is of to the shop and i get a report back.

[spammysammich]

If you have access to a borescope you can drop it into cylinder 3 to look at the valves and cylinder wall for signs of bore scoring.

[spammysammich]

Any updates OP?

[PCG.DTCH]

Originally Posted by spammysammich

Any updates OP?

Hi all, just had an phonecall of a fellow-E92-M3 driver that has experienced the same thing. And i remembered about me not updating this topic. (and the fact that i hate when i stumble on old forum posts about a problem i'm having, and OP not updating their post :P)

And boy, do i have an update. :P

After my ISTA diagnoses, i contacted the stop that carried out the Rodbearings for diagnostics, so i put it on a trailer and hauled it to their shop.



When they did their compression check, they found the same results; Cil. 3 left the chat. Camera showed no damage in the cilinders, so as a result they suggested pulling the engine.

After some time had passed, and they found the time to work on it. The results came in.

They pulled the engine





Called me and made me clear:

1. I'm extremely lucky
2. I'm still going to be poor after the repair.





As you can see, the valve-spring had snapped and the valve had hit the piston - ONCE!

As you can see on the image below, there is no damage to piston #3.



The valvespring snapped, but had still enough "height" to prevent the dropped valve from hitting the piston again, after the initial hit.

It was bend, but ever so slightly.

- I didn't need new heads
- i didn't need a new block

so that's why i'm considering myself lucky. But it was still a pretty big bill. (also due to valveguides, vanos-covers etc being replaced.

And now i've made over 4000km after repairs, it's better then ever!

[charliev68]

Originally Posted by charliev68

I would physically inspect your valve springs on Bank 1 to see if they are broken or fatigued. I know it sucks, but you will have to remove your camshafts. It would be the final step after you have eliminated everything else. Good luck 🍀 and hope it’s something sensor related instead of valve springs.

I’m just saying…I called it! Ask me how I know!!!

[RocketyMan]

Originally Posted by PCG.DTCH

Hi all, just had an phonecall of a fellow-E92-M3 driver that has experienced the same thing. And i remembered about me not updating this topic. (and the fact that i hate when i stumble on old forum posts about a problem i'm having, and OP not updating their post :P)

And boy, do i have an update. :P

After my ISTA diagnoses, i contacted the stop that carried out the Rodbearings for diagnostics, so i put it on a trailer and hauled it to their shop.



When they did their compression check, they found the same results; Cil. 3 left the chat. Camera showed no damage in the cilinders, so as a result they suggested pulling the engine.

After some time had passed, and they found the time to work on it. The results came in.

They pulled the engine





Called me and made me clear:

1. I'm extremely lucky
2. I'm still going to be poor after the repair.





As you can see, the valve-spring had snapped and the valve had hit the piston - ONCE!

As you can see on the image below, there is no damage to piston #3.



The valvespring snapped, but had still enough "height" to prevent the dropped valve from hitting the piston again, after the initial hit.

It was bend, but ever so slightly.

- I didn't need new heads
- i didn't need a new block

so that's why i'm considering myself lucky. But it was still a pretty big bill. (also due to valveguides, vanos-covers etc being replaced.

And now i've made over 4000km after repairs, it's better then ever!

Thank you for reporting back with detailed pictures! Glad you got it sorted. And yes, I think you are pretty lucky given the circumstances.

[charliev68]

Can you tell us the total bill for the diagnostic and repair?
Did they only replace the 1 valve spring?