[bimmer_in_cm]

Originally Posted by TacoCodeRed

I used that after doing about a days worth of research on here.
My initial thought after getting all kinds of random misfires and they never followed the coil swap was the plugs.

Vanos solenoids were also replaced shortly before I bought the car.
Almost everything was including the turbos.
My best friend is also a BMW mechanic so most things he catches but I hate trying to troubleshoot with him when he is outside of work.

All the codes are misfire related. I just swapped in the new coils today and only got those two after about 6-8 runs

Read up on bad mosfets in the dme. I wish that was my prob, unfortunately i have oil on the bottom of #3 plug so im looking at a new engine. I did all the steps that cobb recommended and still had a misfire. Long story short i wasted 1200 bucks for nothing.

[TacoCodeRed]

I actually replaced all 6 mosfets before replacing everything I listed due to 2 of them going bad. So that's no longer the problem (it was a huge pain though)

[bimmer_in_cm]

Originally Posted by TacoCodeRed

I actually replaced all 6 mosfets before replacing everything I listed due to 2 of them going bad. So that's no longer the problem (it was a huge pain though)

My bad!...Well i hope you don"t have an oily plug on the spark side of one of those misfires. My misfire on #3 cyl turned out to be a bad cylinder or bad rings, either way its costing me 4k to fix

[swollix]

Car goes into limp mode and loses power whenever I go WOT. I had the codes read and I am throwing a 29DC code. He rode with me while I was driving and the low pressure hPa was dropping into the 3000 range when I went WOT. At idle it was in the 5,000s and the high pressure pump was always 50,000+. Put in new LOW PRESSURE fuel pump and it is doing the same thing! I noticed the car runs better when it's cold. The first few minutes after putting in the new pump, I was actually able to hit WOT... but once the engine is warmer it goes back to running on three cylinders. Code I keep getting on generic scanner is P142e, once I got a p3090. Car has no issues starting or idling, idles at 600 perfect and starts nearly immediately.

[spyderlinke92]

I did some work on my car today and now I'm getting this dreaded Cylinder 4 Misfire...

The car was bone stock to start. I purchased it about 2 weeks ago, and the guy I bought it from said he just had the spark plugs changed.

Today I installed DPs, DCI and Cobb AP V2. I didn't drive the car between any of the new parts, so I don't know where the problem started, but I'm assuming it's from the Cobb AP. I had no issues at all with the car before any mods, even with hard pulls and WOT. I installed stage 2 sport ST, and immediately threw a CEL at about 3500 rpm WOT in all gears. So I brought it back home and moved to stage 1 drive ST, and having the exact same issue. If I hold about 3/4 throttle, I can go all the way up to 6k rpm and never throw a CEL. I used the AP to clear the code, and the second the CEL was gone, the car started running beautifully again. So again, I dropped the tune down to stage 0 to see if that would stop it, but same issue again. So I gave up. Brought the AP inside and hooked it up to the manager, and sure enough it needed an update. That's as far as I've gotten so far.

The misfire is on Cylinder 4 every time. From reading around the forums, I will try the coil pack swap and see if the issue moves to another cylinder then go from there.

Any other advice besides plugs, injectors and coil packs would be greatly appreciated!

Thanks

[spyderlinke92]

** UPDATE **

I took the engine bay apart today and swapped coil packs between cylinder 2 and 4 (where I was getting the misfire), took it out for a quick test drive and now cylinder 2 is misfiring... so I ran into the parts store and picked up an Echlin coil (part IC682) and replaced it with cylinder 2. Again, went out for a test drive and NO misfire!! Super excited now about that, so I'm installing the AP again and hoping no issues pop back up. Now to just fix the stupid WG rattle, that is much louder now with the DPs installed.

[BRMTDI]

Is your ECU MSD80?

[benton0311]

Trying to determine whether my issue is plugs or coils.

Car: N54, 103k miles, JB4, intercooler, cone filters. Intercooler added at 75k and cone filters at 90k.

My spark plugs (OEM Bosch) are only lasting 10k miles before I get misfire codes and need to replace the plugs. Once I replace the plugs everything is fine until I hit another 10k miles and I get misfires again. Misfires are only under WOT when it appears the spark can no longer overcome the resistance/gap under full boost. The car has been tuned since I bought it new in 2008 and I used to be able to get 15 - 20k on the plugs a few years ago. I begin to get misfires almost exactly every 10k miles – I’d say 10.5k miles for Map 5 and 12k miles for Map 1 before I get misfire codes. Regardless of where the misfire occurs the problem goes away as soon as I change plugs.

My question: do the coil packs actually weaken over time or do they just fail outright (i.e. maybe idle ok but get misfires all over as opposed to only full boost). I used to be under the impression they could weaken and generally seem OK but lately I've been reading they usually either work or they don't and there really is no in between.

I'm trying to determine:
Are the plugs not lasting as long due to driving habits or latest tune update
OR
Have the coils now weakened enough that the spark can't overcome the gap as the electrodes wear after 10k miles of use

I think I’ve ruled out fuel/VANOS/valves since new plugs fix the issue. I just have to replace them more often than I think is normal.

[cwbmw]

Just did a Cobb Stage 1 drive flash...

Car went to shit lol. Misfires cylinder 4, fuel pump warning. Turbos sound like shit when they get to mid-boost and make a weird vibration.

Going to flash back to stage 0 and replace all my plugs/coils and walnut blast intake before tuning again.

Dammit!

[steezus]

Occasionally I'm getting the 30FE over boost code with the accompanying 3100 low boost engaged. Running Map 5 on JB4 G5 ISO. Spark plugs just changed maybe 200 miles ago. It doesn't even happen when I'm at WOT - I want to say it's when I'm getting up in RPMs slowly.
I just had VRSF downpipes put on but the code was coming up before they were installed.

I randomly started logging using the JB4 app and had it running when the code popped up.

I got the JB4 used off a member who had a FBO 335i, so I'm not sure if there's any settings I need to change. Currently only using the app though.

Anyone care to help me figure it out?

http://datazap.me/u/steezus/log-1487...log=0&data=1-4

[e92sidhu]

Hey guys, so i have a 2008 bmw 335i n54 with 93,500k on it- the car has a intake,exhuast and a tune ( which i didnt know it had one til someone told me ) is there anyway to find out what tune ? its not jb+ or jb4... but i just bought this about 2 months ago....under WOT the SES would come on after about 20 mins of driving it, got the car checked out at a well known place they said it was giving vanos intake code, misfire in 1 and 5...
so the stuff i done so have -
- all new 6 plugs
- new coils for 1,5 - they were replaced last year also
-walnut blast done
- cleaned vanos.. shop has been busy so they didnt look more into it yet any suggestions ? thanks!!

[dpaul]

This one seems a little different - perhaps someone has a thought.

Misfire on cylinder 6 that occurs only when engine is cold, very quickly after startup. Happens every single startup without fail. No other codes. Always cyl 6.

Once warm, there are no problems at all, WOT is fine, idle is absolutely smooth

I've swapped, then replaced all the plugs and all the coils. No change. I replaced injector 6 then swapped injectors between various cylinders, replacing the black O-ring at the same time. No change. Also, neither plugs nor injectors ever came out wet and/or black. Walnut blast performed - no change.

Engine is FBO w/ inlets and outlets although JB4 is removed and DME flashed back to stock for diagnosis. Compression and leakdown in in cyl 2-6 are fine; cyl 1 compression is 12% lower than the others. Has a number of new parts installed over the past two years: VANOS actuators (for codes related to VANOS function), DME (for MOSFET failure), DMFW and clutch, boost solenoids, vacuum lines, bank 2 pre-cat O2 sensor.

One last problem is a modest bucking or surging that only occurs at very light throttle at low rpm, as when moving off from a stop. No idea if it is related or not but both issues started occurring around the same time.

Anyone seem anything similar?

[GEOS07335i]

I had multiple misfires on my 08 335i 124k took me a month to figure it out. swapped out coils, plugs, injectors, cleaned vanos silonoids, walnut blasting, compression test. In the end I fixed the issue by swapping out both precat O2 sensors and resetting all adaptations in INPA 2x. Most of my misfires were on BANK 2. O2 sensors only good for 100k. I had no codes for 02 sensors at all. My car is totally stock for now.

[dpaul]

Forgot to mention, had also replaced bank 2 pre-cat O2 sensor (cyl 4-6; it was accidently damaged during downpipe installation). Also want to emphasize, misfire only occurs when engine is cold, almost always on cyl 6. Once warmed up, WOT is fine. Sound like an injector, I know, but injector swap/replacement did not affect the problem.

[GEOS07335i]

Guy's I've also been through the misfire nightmare. And totally understand the frustration your dealing with. What resolved it after I went through new plugs, coils, and ebay injectors was pre-cat O2 sensors. If you have misfires on 2 cyls on the same bank and your car has close to 100-120K you should look at the precat O2 sensor on that bank. I'm no mechanic but it fixed it for me. I did not have any codes that lead me to believe it was an O2 sensor. Just the fact that I had multiple misfires on Bank 2. cyl4 cyl5 and cyl6 at different times and often 4 and 6 at the same time. Look at your old history and see if you have misfires related to the same bank.

Also please post what your fix is after you have nailed it down. Way to often people fix the issue but never report what actually fixed it. Misfire issue on our cars could be 20 different factors and a real pain to troubleshoot.


Just curious if you reset your adaptations after replacing your O2 sensors? I think this helped my car. Not sure this is necessary as your now running catless DP's.

Originally Posted by dpaul

Forgot to mention, had also replaced bank 2 pre-cat O2 sensor (cyl 4-6; it was accidently damaged during downpipe installation). Also want to emphasize, misfire only occurs when engine is cold, almost always on cyl 6. Once warmed up, WOT is fine. Sound like an injector, I know, but injector swap/replacement did not affect the problem.

[tdli]

I have couple of questions:

1. Are coil packs bank/cylinder group specific? Can I swap one from any cylinder to test with another?

2. Just to make 100% sure, no coding needed after new coil packs are installed, correct?

[GEOS07335i]

Originally Posted by tdli

I have couple of questions:

1. Are coil packs bank/cylinder group specific? Can I swap one from any cylinder to test with another?

2. Just to make 100% sure, no coding needed after new coil packs are installed, correct?

1) coil packs are not group specific. Yes you can swap them out for testing thats what we all do for checking misfire issues

2) no coding required for coils. Your thinking of fuel injectors.

[tdli]

Originally Posted by GEOS07335i

1) coil packs are not group specific. Yes you can swap them out for testing thats what we all do for checking misfire issues

2) no coding required for coils. Your thinking of fuel injectors.

Thanks so much!

[omniscient87]

I'm new to this platform but have about 15 years of experience with tuning cars. I just picked up an 09 335 xdrive, I installed MHD and did some logs of a stage 0 tune and my AFRs are in the mid 13's under boost and I'm getting timing correction on all cylinders. I just want to get some input from my logs.

[n54ordie]

I have been having some drivetrain issues (maybe) and am too much of a noob to create my own post at the moment. My car took a dump on me a month ago and as I've been waiting for my Spec stage2+ clutch kit and MFactory SMF to come in, I installed bolt ons, MHD tune and koni shocks and struts replacing all bushings on the way. I took my car to BMW of SD for a diagnostic when I suspected the clutch went out (Huge clank with a drop feeling) accelerating after a turn. I did the clutch and with my rear tires up, went through reverse, 1st and 2nd gear smoothly it all sounded good. With the car on the floor, I get this clanking sound coming from where the driveshaft meets the rear differential and cant really accelerate. Somebody help please!

Thanks here is a video of the issue with general description.

[beetle6986]

The misfires and other problems on these cars is exhausting. The amount of time I spend replacing coils, plugs, injectors, vanos, water pumps, crank position sensors is 10 times what I spend on my FORD Mustang.

Mine is now misfiring mostly under light load or at idle. Most of the time it behaves well under WOT conditions.

I replaced the valve cover gasket (was leaking pretty bad) all the plugs, coils and the exhaust Vanos. I cleaned the intake Vanos. It is better, but the car still misfires pretty bad sometimes. It doesn't seem to be consistent. Some days are good and some are no so good. I think hot days seem to be the worse.

[b92]

Originally Posted by beetle6986

The misfires and other problems on these cars is exhausting. The amount of time I spend replacing coils, plugs, injectors, vanos, water pumps, crank position sensors is 10 times what I spend on my FORD Mustang.

Mine is now misfiring mostly under light load or at idle. Most of the time it behaves well under WOT conditions.

I replaced the valve cover gasket (was leaking pretty bad) all the plugs, coils and the exhaust Vanos. I cleaned the intake Vanos. It is better, but the car still misfires pretty bad sometimes. It doesn't seem to be consistent. Some days are good and some are no so good. I think hot days seem to be the worse.

I was in the same boat, i highly recommend switching to JB4+MHD backend, this will solve your timing issues