[jonas]

Ok guys, I installed the JB4, and almost like clockwork, I killed the #5 ignition coil. No biggie, swapped, and we were off again. Now I have a curious problem. I get a #3 cyl misfire code, but only if I go WOT. The car throws a code, and JB$ does its job and reverts to map 4. Is this common to only get the misfire under WOT? The car is perfectly fine under normal driving conditions, and if I ease into the throttle, I can get into 120ish MPH without the misfire code being thrown. But the second I try to floor it from rolling, I get the code. So, whats up? Maybe a spark plug, or am I replacing another coil?

[PR3CI5N]

If you have replacement spark plugs swap out cyl 3's. Should be good to go after

[jonas]

I don't have replacements, but I can acquire a few!

Quick Questions: Wheres a good place to pick up that BMW spark plug socket locally? I'd like to put hands on it, rather than wait on shipping and silliness...

[PR3CI5N]

BMS sells the socket along with the plugs

[jonas]

Originally Posted by PR3CI5N

BMS sells the socket along with the plugs

I want to grab it locally. Like at an autozone, or somewhere similar. I want to do this project this weekend, and shipping isn't gonna put that in my hand come Saturday afternoon...

[blown07]

The more cylinder pressure there is (higher boost) the harder it is to jump the gap on a spark plug. This is most likely when a coil will misfire. I had this happen twice and had to replace two different coils as they were originals. When the misfire happened it would continue to misfire until I shut the car off and restarted. After the restart the car would run perfect under low load. Never did understand why the coil would continue to misfire once the load was removed however.

[PR3CI5N]

Originally Posted by jonas

I want to grab it locally. Like at an autozone, or somewhere similar. I want to do this project this weekend, and shipping isn't gonna put that in my hand come Saturday afternoon...

No idea where you can buy it locally. If you do find one local make sure it's magnetized so that the spark plug doesn't fall out of the socket. Good luck

[jonas]

Originally Posted by blown07

The more cylinder pressure there is (higher boost) the harder it is to jump the gap on a spark plug. This is most likely when a coil will misfire. I had this happen twice and had to replace two different coils as they were originals. When the misfire happened it would continue to misfire until I shut the car off and restarted. After the restart the car would run perfect under low load. Never did understand why the coil would continue to misfire once the load was removed however.

Curious... Because if I reset the codes through the JB4 controls, the car idle smooths right back out, and it runs normal. But if I leave the code up, the car shakes like my diesel truck. So I'm exceedingly curious. But I'll try the swap method for coil packs, and I'll get the socket tool online. My search has not given any secret sources for the socket in the local area.

[jonas]

Went ahead and ordered the tool, and it'll be here next week, while I'm leave. Now to do a search on exactly which spark plugs these things take. It's been three years since I drove something with spark plugs...

[Evochuck]

NGK 5992 is the one step colder replacement

http://blog.protuningfreaks.com/2013...m-ilzkbr7a-8g/

[MM Performance]

You can buy the coils and vanos solenoids (sometimes issue if misfire code with vanos code) at autozone and they are covered under lifetime warranty. I am fitting 21psi high rpm misfires and already replaced all could and plugs and checked injectors. May be cam bearing ledge in my case.

[brewnami]

It's 100% spark plugs. Coils are bad from start and spark plugs are bad under WOT usually. I couldn't find a place locally to buy the tool, but the BMS one came in like two days. I don't think the dealer sells them, Sears doesn't stock them in store, just online...

[drewnel22]

Originally Posted by Evochuck

NGK 5992 is the one step colder replacement

http://blog.protuningfreaks.com/2013...m-ilzkbr7a-8g/

I don't think he needs that...no reason to on a simple bolt on car.

Here is a set from ECS. http://www.ecstuning.com/BMW-E90-335...3.0L/ES257800/
I love their website because they have everything very organized and its very easy to find.

[blown07]

Originally Posted by brewnami

It's 100% spark plugs. Coils are bad from start and spark plugs are bad under WOT usually. I couldn't find a place locally to buy the tool, but the BMS one came in like two days. I don't think the dealer sells them, Sears doesn't stock them in store, just online...

The two original coils I changed were just weak and worked no problem out of high boost and from what I have read this is very common. My spark plugs only had around 5kkm on them at the time. It would appear based on my experience and other that when the ECU detects misfire it shuts the coil off until the car is restarted (my case) or until the code is reset (OP's case). It's possible the electronics in the coil are doing this (doubtful) or just the physical coil possibly cooling down and then coming back on line.

[suprchrgd]

i have been chasing a #6 misfire. didn't matter what i swapped around still misfire in #6. I found that i was over boosting post shift which causes timing and fuel to cut off. without seeing a log i can't say this is whats going on, but might be something to look into. I had to adjust my "autoshift boost reduction" setting from 60 (default) to 80. Also check your boost fail safe setting to be sure your not going over that set point...

[Jeff@TopGearSolutions]

Originally Posted by jonas

Went ahead and ordered the tool, and it'll be here next week, while I'm leave. Now to do a search on exactly which spark plugs these things take. It's been three years since I drove something with spark plugs...

Your problem is likely spark plugs as they need to be changed every 25,000 miles on tuned vehicles.

You can buy OEM Bosch plugs or aftermarket NGK which most of us vendors sell. The NGK need to be manually gapped. Otherwise OEM/BMW Bosch plugs are perfectly fine. It's typical for these misfires to happen at WOT.

This sounds like an interesting story, how did you get around for the past 3 years before this vehicle?

[chepy24]

i started to get misfires once i went to e50..... knew it was coil right away swapped one out then another started to misfire. Swapped that one as well and then another one misfired ended up just relpacing all of them no misfire since

[drewnel22]

Originally Posted by Jeff@TopGearSolutions

Your problem is likely spark plugs as they need to be changed every 25,000 miles on tuned vehicles.

You can buy OEM Bosch plugs or aftermarket NGK which most of us vendors sell. The NGK need to be manually gapped. Otherwise OEM/BMW Bosch plugs are perfectly fine. It's typical for these misfires to happen at WOT.

This sounds like an interesting story, how did you get around for the past 3 years before this vehicle?

Diesel...lol

[jonas]

Originally Posted by Jeff@TopGearSolutions

Your problem is likely spark plugs as they need to be changed every 25,000 miles on tuned vehicles.

You can buy OEM Bosch plugs or aftermarket NGK which most of us vendors sell. The NGK need to be manually gapped. Otherwise OEM/BMW Bosch plugs are perfectly fine. It's typical for these misfires to happen at WOT.

This sounds like an interesting story, how did you get around for the past 3 years before this vehicle?

This is my previous Daily Driver. Needless to say, getting a 335i is a drastic swing for me. 8 MPG just wasn't cutting it for my daily commute...

[jonas]

Originally Posted by blown07

The two original coils I changed were just weak and worked no problem out of high boost and from what I have read this is very common. My spark plugs only had around 5kkm on them at the time. It would appear based on my experience and other that when the ECU detects misfire it shuts the coil off until the car is restarted (my case) or until the code is reset (OP's case). It's possible the electronics in the coil are doing this (doubtful) or just the physical coil possibly cooling down and then coming back on line.

^This makes a ton of sense, and I was curious, as one of my work colleges had suggested this theory. It makes sense to me

[jonas]

Originally Posted by chepy24

i started to get misfires once i went to e50..... knew it was coil right away swapped one out then another started to misfire. Swapped that one as well and then another one misfired ended up just relpacing all of them no misfire since

Originally, when the coil went bad for me, it threw a specific code related to the coil pack. This one is only for a misfire, not specific to the coil pack. Thus why I am after a spark plug theory.

[jonas]

Originally Posted by 10splaya22

Diesel...lol

Beat me to it!