[GAM]

Hi everyone,

Got the JB4 and DCI on my 2008 335i with 70k miles, everything was great until last night. The engine was misfiring under WOT and even more under WOT in low RPMs running map 1. If I keep pushing I get the Service Engine Soon and creates a code: cylinder 3 misfiring.
I inverted coil 3 with coil 1 this morning, deleted the codes, and still have the same problem and still showing the cylinder 3 misfiring. Spark plugs have 23000 miles. It doesn't seems to misfire while on Map0 so stock boost. Idle is perfect, car runs great if you dont push it hard.
When I removed the coil number 3, I noticed some oil on it, no oil on the coil one tho.

I hate to feel the car like this, any help or past experience input would be greatly appreciated

Thank you!

[marv85]

are you sure it's oil? I've read about leaking injectors causing misfires

[seetully]

Originally Posted by Gfabry

Hi everyone,

Got the JB4 and DCI on my 2008 335i with 70k miles, everything was great until last night. The engine was misfiring under WOT and even more under WOT in low RPMs running map 1. If I keep pushing I get the Service Engine Soon and creates a code: cylinder 3 misfiring.
I inverted coil 3 with coil 1 this morning, deleted the codes, and still have the same problem and still showing the cylinder 3 misfiring. Spark plugs have 23000 miles. It doesn't seems to misfire while on Map0 so stock boost. Idle is perfect, car runs great if you dont push it hard.
When I removed the coil number 3, I noticed some oil on it, no oil on the coil one tho.

I hate to feel the car like this, any help or past experience input would be greatly appreciated

Thank you!

swap plugs next, ya already swapped coils so thats the next step.. then try to recreate the problem..

[themyst]

if you're only misfiring under WOT, it's plugs since you already eliminated the coil packs. If you get cold start misfires, it's likely injectors.

These stock plugs have greatly varying lifespans IMO. Some may require new plugs in 20-25k miles, but there are others who can go on forever on a set of plugs. I have 32k miles on my plugs FBO+meth and still haven't misfired. I got a set of new plugs, ATF fluid drain, coolant, oil filter/7qts all waiting to go at once when these Rob Beck turbos come in.

[GAM]

Thanks for all the response, coil 3 had oil color on it, or might be fuel but the it was dirty (oil color).
I bought a new set of plugs today and will install them tomorrow, hopefully that will make it.
I can reproduce the problem only when I'm running map 1 on the JB4 (11psi boost), no problem on stock.
And I forgot to mention that when I pull on map1, and get the light on, the car vibrates, feels like no power and misfire big time, thats when I usually get the Cylinder 3 misfire code..

[ZondaF355]

I have been having the exact same problem that your are explaining to a T. I just ordered new plugs and will install them soon as my socket comes in mail. Friend of mine had same problem and got his HPFP recall done and it fixed his misfire issues. One thing I cant figure out is how well the car runs with 110 octane race gas mixed in with 91....This blows my mind. The thing absolutely runs perfectly amazing with race gas mixture in MAPS 0-7 using JB3...I dont know why this is happening but would love for an explanation from someone that knows for sure...Ive come to the point that im not sure if anyone REALLY knows exactly what causes some of the misfire issues. Any input would be greatly appreciated. Thanks and have a good one

[lostomni]

I agree. From experience, change the plugs. gl

[LivnLife31]

Definitely a plug- just had cylinder 5 misfire. Car would stutter and shake over 4500 RPM and SES. Changed cylinder 5 plug- car runs awesome!

BTW- just had plugs changed at dealer less than 5,000 miles ago!

[GAM]

Hi guys, here is today's update.
I did swap fuel injector 2 with 3, I had a misfire on cylinder 3, then deleted the codes and took the car out for a few pulls, same problem but the codes were showing a misfire on cylinder 2 now. I didn't change the plugs yet because I'm waiting for the socket, but the bad injector was black when I pulled it out..

[joed1]

Although I never had any misfiring it was recommended by my service tech to change out the plugs. He said that the turbos are tough on plugs and best to change'em out 20-25K.

[GetSomeE92]

Originally Posted by Gfabry

Hi guys, here is today's update.
I did swap fuel injector 2 with 3, I had a misfire on cylinder 3, then deleted the codes and took the car out for a few pulls, same problem but the codes were showing a misfire on cylinder 2 now. I didn't change the plugs yet because I'm waiting for the socket, but the bad injector was black when I pulled it out..

Did you re-code the injectors after swapping them? If not, I didn't think you could just swap them around like that.

[enrita]

Originally Posted by GetSomeE92

Did you re-code the injectors after swapping them? If not, I didn't think you could just swap them around like that.

You also need to replace the small gasket and ring when you take them out otherwise they will leak pressure out....

[GAM]

Hi guys, here is an update:
Went to a shop today, did install the new plugs, coded the injectors and did a valve cover treatment. Not an inexpensive package but the car runs much better now, just wishing the valve cover treatment would have been done every 15k miles by the previous owners...
Sometimes I still have a little hesitation under WOT but it might be the other injectors getting old or the carbon deposit on the valves, they told me only one treatment done at 70k is not enough to get everything out

[hondaon110]

Where can i buy that socket from?????????