[Zuluaga]

Hey guys.
2009 E93 6 speed with FBO cobb stg2+

Car ran great and all of a sudden I felt a hessitation in 3rd gear around 4500 rpms and it threw a misfire cyl 5 about 3 times. So I swapped the plugs and sure enough the problem followed the first time, but now it actually went back to the original cylinder.

What do you guys think? I ordered all the plugs and plan to change them today. I want to order 2 coils ( one for cylinder 5 and one for cyl 1 since its the one I swapped the coils to and actually had the misfire code on cyl 1 show up once.

So what do you guys think? I did a quick log this morning when it threw the code and this is what came up

thanks in advanced

[psmitty95]

Swap coils to see if the misfire follows the coil. If it doesnt then it's most likely an injector

[Mike@N54Tuning.com]

I would swap the plugs and then re-evaluate.

If it continues the swap the coil from the problem cylinder and see if it follows the coil or stays on the same cylinder. This should give you a pretty good idea of what the issue is.

Mike

[Zuluaga]

I just swapped the coil and it followed immediately, but only once. After I reset the code, it stayed in the same cylinder from the original problem and never went back to the swapped coil.... thats what has me wondering

Did you guys get anything from the datalog?

[JStang]

Originally Posted by Zuluaga

I just swapped the coil and it followed immediately, but only once. After I reset the code, it stayed in the same cylinder from the original problem and never went back to the swapped coil.... thats what has me wondering

Did you guys get anything from the datalog?

Could be an injector.

[Blackhawk36]

How many miles on the car? My guess is carbon buildup in the intake ports.

[vertigo44]

How many miles do you have total. And with the Tune?

Plugs, Coils, Injectors --- Intake valve cleaning could help the car to idle and run smoother but as far as a misfire i doubt it.

[Jeff@TopGearSolutions]

So you swapped coils or plugs? Cause it says plugs first but then you mention spark plugs and then coils.

OY!

Anyway

Change all your spark plugs first. Then if the problem persist on 1 cylinder, move the coil pack to another cylinder and see if the problem moves.

If you swapped coil pack on Cylinder 1 to cylinder 5 and the misfire moves then you need to change that coil pack.

Ideally, you want to change all coilpacks but that can get rather pricey.

If swapping a coil doesn't do anything it could be an injector or a need for an intake valve cleaning.

Intake valve cleanings historically are needed as early as 35,000 miles.

[Zuluaga]

aye... scary if I have to go to the injectors cause I know it can be painful to get the re-coded.

Im sorry I wasnt clear from the beginning. I only swapped the coils since I was waiting on the spark plug removal tool- which I got in today. The original issue was with cylinder 5. I swapped the coils from 5 ( second to last/closer to the firewall) to cyl #1 (closest to headlights)
When I swapped it, I tried replicating the issue and it did come up under Cyl #1, so I thought for sure it was the coil, but after that day- it never came back as Cyl #1 misfire, but came back as the old Cyl #5, which lead me to think spark plugs.... Im swapping all spark plugs today and hopefully it doesnt come back- but if it does, then I guess its the injector??

I have 44K miles and its been tunned since 35K. I do drive very moderately though and absolutely 0 track/racing days. Just the spirited leaving the onramp every now and then.

[Zuluaga]

UPDATE for future reference.

changed spark plugs and car runs like a champ!

The plugs didnt look bad. Number 6 cylinder look more black than the others, but still- all looked great with zero signs of detonation. I do drive my car very easy and dont beat on it, so it was expected.

Thanks for all the help guys!

PS: I can change my spark plugs now in 15 mins! hahah first time I took all those panels off took me like 2 hours