[Blueeyesredpanda]

I have a cylinder 2 misfire, so I swapped the coil 2 to 3 and 3 to 2. So the problem went to cylinder 3, then I scanned the car again, cylinder 4 has a misfire.

So I change the coils for cylinder 3 and 4, start up smooth, but yellow engine light is still there. I went for a drive and it was smooth for 5 mins, then the vibration came back again. Scanned the car, said its cylinder 3 and 4 misfire. Then I swapped spark plug from cylinder 3 and 4 to 1 and 2. Started the car again, reader says cylinder 3 and 4 misfire again.

What should I do next ?

328i 2010 69000km

[N55Jamaican]

Just replace all 6 coils. END OF STORY

[Blueeyesredpanda]

Originally Posted by N55Jamaican

Just replace all 6 coils. END OF STORY

But why does cylinder 3 and 4 still misfire after I replaced the coils

[GATORB8]

How did the plugs look?

[Blueeyesredpanda]

Originally Posted by GATORB8

How did the plugs look?

I pulled out the spark plug from cyl 3 and i remember cyl 1 and 2 spark plugs were so clean comparing to cyl 3 spark plug.

[GATORB8]

Wet? Smell like oil or gas?

[BashShah]

After Sparkplugs and Coils, you should do an Adaptation reset.

[Wolf 335]

Originally Posted by DarkNemesis

After Sparkplugs and Coils, you should do an Adaptation reset.

What adaptation?

[Phil325i]

Originally Posted by Wolf 335

What adaptation?

+1

Changing plugs and coils does not require a re-set. Looking at that plug I'd say you may have an injector issue...

[tcphoto]

I've only owned my E92 for six months and I am still learning about it. But, after nearly seven years in an E46, I learned that misfires can be caused by vacuum leaks also. I'd start replacing hoses just for good measure and coils while you're at it.

[BashShah]

Originally Posted by tcphoto

I've only owned my E92 for six months and I am still learning about it. But, after nearly seven years in an E46, I learned that misfires can be caused by vacuum leaks also. I'd start replacing hoses just for good measure and coils while you're at it.

Blueeyesredpanda has a 328i.....what Vacuum does this car have?......a BLOCK leak?....then would be getting AFR Bank 1&2 Codes.
and he has a scanner....what scanner are you using.

How much Gas do you have in your Tank?
if nearly Empty......GOOD.
go to Cheveron and fill up with their BEST most Expensive Gas.
We just want Techron.

If you tank is half or more.....then get 2 bottles of Chevron TECHRON Concentrate.....not the costco non concentrate stuff.
their are other solutions, but the idea is to clean your Injectors.

why 2 bottles, 2 tanks.....back to back.

you already changed plugs and coils.
now if you miss matched your coils, like old and new....then don't know.
There is a Life to Coils and Plugs.
when I get a used car.....I change them....Period....then I know when to do it again.

I recommend changing all.

also you have swapped good and Bad...and the Problem stayed.....be sure you were not looking at old codes.

since you swapped them....the only remaining items are:
Injectors and MAF.
or even Air Filter.

just curious what Plugs and Coils are you using?

Adaptation reset is sometimes necessary to let the DME relearn control Values.
look up bmwlogger free version.
Look up INPA installation.

Keep us posted.

[lab_rat]

Do you have a leaking VCG? Sometimes it begins to leak around the spark plug area and will seep into the spark plug well...maybe that could be causing the issue with cylinders 2,3 & 4?
Peer in the wells with a flashlight and see if you notice any oil; also check the entire perimeter of the VCG, including next to the firewall.

[E90dima]

Over torqued them. Once over torqued, the spark plugs are damaged. Get new spark plugs. Ask me how I know

[STR8-6IX]

Originally Posted by Phil325i

+1

Changing plugs and coils does not require a re-set. Looking at that plug I'd say you may have an injector issue...

transmission adaptation reset? why? that does not make any sense.

[Denny Swift]

Originally Posted by E90dima

Over torqued them. Once over torqued, the spark plugs are damaged. Get new spark plugs. Ask me how I know

I know this is a really old post, but I'm adding to it to help others.

I changed my plugs, carefully torqued each to 17 ft-lb, and then had a misfire in cylinders 5 & 6. I used OEM BMW Bosch plugs. I just couldn't figure it out. I've changed plugs dozens of times over the decades and this just made no sense to me. So I removed the two suspect plugs and replaced the originals. I still had a misfire. I swapped coils, but the misfire stayed. I bought two new plugs, put them in cylinders 5 & 6, and I STILL had a misfire!

This is the strangest car maintenance/repair experience of my life. Google searches led me here. Also, I put a small dab of antiseize on each plug as I have always done. Various sources say that, that could require reducing the torque by 20%. Even so, that would equate to about 20.5 ft-lbs. I have a really hard time believing that 3.5 excess ft-lbs could really cause the issue. (The spec is 17 ft-lbs +- 2.2).

After exhausting all other possibilities, I bought NGK Iridium plugs, installed them without antiseize and torqued them to 15 ft-lbs (I assume a bit of antiseize remained on the head threads.)

Car now purrs like a kitten. I drove it about 100 miles with my scanner set to live mode. Not one misfire in any cylinders. Was it really that such a wee bit of over torque could have cracked them? I'll never know for sure, but I just can't imagine that the Bosch plugs are that sensitive. (I talked to the local BMW service manager, and he thinks the extra torque was the problem).

Anyway, I figured that I'd share my story to help others.