Misfiring Cylinders 5-8 After Replacing Starter

Posted in wrong section so reposting here...

I was having issues with my starter & as a result went ahead & replaced it following some DIY's. I had done the actuators & other components in that area many times before so I felt confident doing it myself.

I replaced the starter, had a bit of an issue getting the plenum back on for the first time ever, but ultimately popped it on & the car started up like butter.

After driving it for about a day, I began to smell fuel inside of the cabin. This never had happened before changing the starter. Additionally, it appeared as if the idle had be a bit rougher on the side of the driver.

Upon a family member driving it today, out of nowhere, the car went into limp mode & after running bimmerlink, these codes came out:

27B2: Secondary air system throughout main line
2B39: Misfiring with shutdown Cyl. 5
2B3A: Misfiring with shutdown Cyl. 6
2B3B: Misfiring with shutdown Cyl. 7
2B3C: Misfiring with shutdown Cyl. 8th
2B41: Misfiring with shutdown several cylinders
2B57: Engine emergency program activated
2796: Engine emergency program activated

In addition, I've had this code for forever & always clear as I was told it's not really an issue: A6D1: Additional Water Pump


Now, based off of what I've read, it seems like there could be a few a problems, but I am unsure as this happened to occur after I replaced the starter. With the first code, I am assuming that I must not have connected the air hose properly. But would that lead to the engine misfires & the smell of fuel? Reading that it could also possibly be a leaking exhaust gasket above the O2 sensors... but it's just odd that the smell of fuel would happen exactly after replacing the starter.

Any thoughts or recommendations as to what I should tackle & check?

Check grounds for a misfire after you’ve done maintenance that could affect it, ie disconnecting a ground point. Fuel smell could be a result of the misfire.

I’m unapologetically the “check your grounds” guy. I chased a misfire for an while only to find a grounding nut was missing on the engine harness, hoping it’s something easy like that for you.

fs34 wrote

Check grounds for a misfire after you’ve done maintenance that could affect it, ie disconnecting a ground point. Fuel smell could be a result of the misfire.

I’m unapologetically the “check your grounds” guy. I chased a misfire for an while only to find a grounding nut was missing on the engine harness, hoping it’s something easy like that for you.

I was in a similar spot before, which is why my starter need a replacement now. My car was struggling to crank, turned out it was the ground underneath the car.

Hopefully I can check it out soon.

Codes have been cleared & still haven't come back, but I am expecting them to eventually, as the smell of fuel is still there, predominantly coming from the driver's side front wheel area.

pzzvv wrote

I was in a similar spot before, which is why my starter need a replacement now. My car was struggling to crank, turned out it was the ground underneath the car.

Hopefully I can check it out soon.

Codes have been cleared & still haven't come back, but I am expecting them to eventually, as the smell of fuel is still there, predominantly coming from the driver's side front wheel area.

Check the main fuel line connection — it’s on the driver side.

kolosy wrote

Check the main fuel line connection — it’s on the driver side.

https://www.m3post.com/forums/showthread.php?t=1744228

This right here? Going to have a look tomorrow so want to make sure it’s the correct part.

No, on the strut tower

kolosy wrote

No, on the strut tower

Checked it, seems fine. The smell went away for a bit & seems to be more faint now.

Single bank misfires are usually exhaust related. I'm thinking it's your exhaust gasket. Would also correlate with the smell coming from driver (left) side.

pzzvv wrote

Posted in wrong section so reposting here...

I was having issues with my starter & as a result went ahead & replaced it following some DIY's. I had done the actuators & other components in that area many times before so I felt confident doing it myself.

I replaced the starter, had a bit of an issue getting the plenum back on for the first time ever, but ultimately popped it on & the car started up like butter.

After driving it for about a day, I began to smell fuel inside of the cabin. This never had happened before changing the starter. Additionally, it appeared as if the idle had be a bit rougher on the side of the driver.

Upon a family member driving it today, out of nowhere, the car went into limp mode & after running bimmerlink, these codes came out:

27B2: Secondary air system throughout main line
2B39: Misfiring with shutdown Cyl. 5
2B3A: Misfiring with shutdown Cyl. 6
2B3B: Misfiring with shutdown Cyl. 7
2B3C: Misfiring with shutdown Cyl. 8th
2B41: Misfiring with shutdown several cylinders
2B57: Engine emergency program activated
2796: Engine emergency program activated

In addition, I've had this code for forever & always clear as I was told it's not really an issue: A6D1: Additional Water Pump


Now, based off of what I've read, it seems like there could be a few a problems, but I am unsure as this happened to occur after I replaced the starter. With the first code, I am assuming that I must not have connected the air hose properly. But would that lead to the engine misfires & the smell of fuel? Reading that it could also [...]

I’m with the suggestions above - Misfire on Bank 2 (Driver side in the US) could be because of missing grounding of 2 cables on that side.

The fuel smell could be hoses relating to the the tank ventilation valve not sealing properly after removal. Let us know what you find.

Hi pzzvv
Managed to solve this issue?

Providing a follow up as it now seems I'm having larger issues, with the car now NOT starting at all. I had previously cleared those codes & the car was running fine out & they did not come back up until today.

Upon running bimmerlink these for the codes that I now have.

27B2: Secondary air system throughout main line
2B39: Misfiring with shutdown Cyl. 5
2B3A: Misfiring with shutdown Cyl. 6
2B3B: Misfiring with shutdown Cyl. 7
2B3C: Misfiring with shutdown Cyl. 8th
2B41: Misfiring with shutdown several cylinders
2B57: Engine emergency program activated
2796: Engine emergency program activated

^^^ these are all back & these are the additional new codes that came.

27AB: Fill plausibility diagnosis warm - Bank 2
CDB8: Message 0xB8 (moment request dual-clutch gearbox)
CD9D: Message 0xBA (transmission data)
CDB4: Message 0x3B1 (transmission data 3)
CD93: Message 0x1A2 (transmission data 3)
278D: Generator communication
D357: D357 - PT-CAN Transmission 1 - Transmission data message 186 missing
E09B: Message from the EGS is missing: Display of transmission data LIN bus
E094: Message from the EGS is missing: Display of transmission data PT-CAN
A3AA: CAN_ID_1D2_ERROR_Botschaft_getriebedaten


Seems like a transmission issues but the car is stuck at the grocery store lol. So i need to have it towed but debating if the tow is going home or if it's going to a shop.

Now, when replacing the starter I did encounter one thing. Inside of the engine block, where the throttle actuators are, was an entire nest that was either from chipmunks or mice. My guess is chipmunks. I have zero clue how they got in there. While I did not see any issues with wires etc. inside of there, I wouldn't discount that as a possible issue.

pzzvv wrote

Now, when replacing the starter I did encounter one thing. Inside of the engine block, where the throttle actuators are, was an entire nest that was either from chipmunks or mice. My guess is chipmunks. I have zero clue how they got in there. While I did not see any issues with wires etc. inside of there, I wouldn't discount that as a possible issue.

Rodent damage is usually covered by your insurance carrier. Definitely worth checking with them. I say that because rather than debug each wire and electrical connection, the section of the loom feeding the TAs, ICV, injectors etc. may need to be entirely replaced. The smell of mint oil is a deterrent to many rodents. Bad TAs, or their wiring can throw all sorts of codes. Your Dealership will be quite familiar with the issue or rodent wiring damage. I think it was around 2006 or so the EU passed some rule about car part recycling and car makers responded by using wiring insulation formulated with soy in it. Hence, the relatively new issue of rodent snacking on the looms. Perhaps that's not the issue but then again perhaps the critters also messed up your starter motor. Be glad you found the nest before they entered the dash.

Are you absolutely sure that the two grounds to the valve cover gasket on the driver side are connected securely? They should be next to the #8 coil. What is your battery voltage? Wholesale weird fault codes start popping up with battery failure.

spammysammich wrote

Are you absolutely sure that the two grounds to the valve cover gasket on the driver side are connected securely? They should be next to the #8 coil. What is your battery voltage? Wholesale weird fault codes start popping up with battery failure.

I'll take a peek in a couple days as i had to leave town, but from what i recall all that i did under the hood is proper.

I had a buddy come by & clear the codes & i was able to get the car started, but it only had first gear & reverse. Additionally, while driving none of the gauges worked. The windshield wipers were running on their own.

The battery was replaced not even a year ago but I will check the voltages.

If the battery was not registered you can over charge and hurt it relatively quickly, or the car sits a lot untendered it can drain deep enough to hurt a cell. Your symptoms are too numerous. See if you can find a wiring diagram from ISTA to see if they boil down to a module or circuit that is particularly sensitive to low voltage. Note, coding a battery is NOT the same thing as registering. A lot of people mistakenly use the terms interchangeably. Very different functions.

spammysammich wrote

If the battery was not registered you can over charge and hurt it relatively quickly, or the car sits a lot untendered it can drain deep enough to hurt a cell. Your symptoms are too numerous. See if you can find a wiring diagram from ISTA to see if they boil down to a module or circuit that is particularly sensitive to low voltage. Note, coding a battery is NOT the same thing as registering. A lot of people mistakenly use the terms interchangeably. Very different functions.

I'm in the northeast & the car is usually between the garage & the driveway. It doesn't sit on a tender. I either registered OR coded the battery through bimmercode/link, but I am not sure which I did. I try to do as much on my own as I can (I'm not a pro) but it's possible I did something wrong in the battery process.

I'll have to download ISTA & see what I can do as I was able to get the car back into the garage. It is just a bit odd how I had the misfires & smell of fuel/exhaust when I first created the thread, & now I have the DCT failure.

Possible that it could be a busted FRM module? I have had small electronic issues in the past such as tail lights going out & had an inclination that the FRM could be going bust.

If you replace the battery with oem or same type/amps as stock there would be no reason to code it. Only register it which is done in bimmerlink

Battery voltage on the lower end but is fine. Car is still sitting as I haven’t had time to do much w it but noticed my coolant had been leaking. Any electronics in the path of coolant hoses that could be directly impacted?

These are the codes that I am getting now. When turning ignition the wipers just run on their own. Has to be electrical as previous codes have disappeared.

pzzvv wrote

These are the codes that I am getting now. When turning ignition the wipers just run on their own. Has to be electrical as previous codes have disappeared.

I recall you mentioned above finding a rodent nest in the V of the engine block around the area of the TAs. Have you inspected the wiring looms in that area?
.

Low end of battery voltage is absolutely not “fine”. You get all sorts of com errors between modules if the battery voltage is low. As evidenced by your whole slew of CAN bus errors. Charge the battery up all the way, clear errors and see what recurs. Then get your battery and alternator tested.