[BEAR-AvHistory]

I use a normal deep socket, 3/8" ratchet with extension, hemostat, a short piece of fuel hose & a 3/8" drive torque wrench to change the plugs. Socket removes plug from the cylinder head threads. Hemostat grabs it to lift it out of the tube.

Rubber hose is pushed on the end of the new plug to hand tighten it in the head. Socket with torque wrench tightens it up. No rough idle or thrown codes.

[bavaddict]

Originally Posted by BEAR-AvHistory

I use a normal deep socket, 3/8" ratchet with extension, hemostat, a short piece of fuel hose & a 3/8" drive torque wrench to change the plugs. Socket removes plug from the cylinder head threads. Hemostat grabs it to lift it out of the tube.

Rubber hose is pushed on the end of the new plug to hand tighten it in the head. Socket with torque wrench tightens it up. No rough idle or thrown codes.

Curious if your plugs were geniune BMW or OEM Bosch?

[335i E92]

Originally Posted by Stein67

Just a curiosity, but has anyone who replaced plugs, immediately got a rough idle simply put the old plugs back in to see if it promptly goes back to a steady idle?

Unfortunately my garage threw the old ones away.

Originally Posted by bavaddict

Curious if your plugs were geniune BMW or OEM Bosch?

I have tried Bosch OEM and the ones with BMW stamped on and neither have cured the rough idle.

Car is going in on Friday to check plug gaps and investigate a possible leaking injector or air leak.

My problem is definitely a misfire that is only present at idle and is causing the occasional long crank or stumbling / stuttering in to life on start up. All points to fuel not being ignited and flooded into the exhaust causing a puff of black smoke on start up.

This either has to be an incorrect fuel / air mixture caused by an air leak or leaking injector or a lack of spark from a plug.

Either way my local Indy have put a few hours aside on Friday to really dril down in theses areas.

Will report back Friday afternoon.

[335i E92]

Update...

Took my car in today!!

So , I've done 800 miles on my new plugs and they all look great apart from cylinder 6 plug which was coked up to f@&k. We put a camera down and could see that the injector was spraying a fine mist of fuel each time the pump was primed. This has been the cause of black smoke on start up as the cylinder was constantly flooded. So we replaced the injector and started her up and the rough idle shakes are still there. Bo@&ocks!!

So looks like I had 2 problems, at least we identified the leaky injector. Both ex BMW head techs an my local Indy agreed it was time to go back to basics and as the rough idle started immediately after changing the plugs 18 months ago this is where we should focus. It had 3 different sets of Bosch / BMW oem plugs and none have cured the issue. They want to try an NGK single prong plug that other 335i owners have used successfully to solve misfires. They are straight out of a 2008 mini cooper s.

Going back next sat to reinspect cylinder 6 to confirm no more carbon build up and then try these's NGK plugs. My techs said that BMW change the specs of their plugs constantly and my car seems to be struggling to adapt to them.

Anyone else heard of these NGK cooper s plugs?

H

[bavaddict]

Looks like someone in your new thread mentioned that u may have starting issues with those plugs....but if try it out regardless let us know. If it works I may try it as well.

Good luck.

[335i E92]

Update...

The car went back a week after having the new injector and the plug was clear and clean so it looks like i had a leaking injector which was seperate to the rough idle issue.

I had master BMW tech look at my car and after a good hour or so of discussing how the rough idle started and what had allready been replaced he thinks a special reset needs to be done to help the adaptation of the new plugs.

This isn't a standrd reset and can only be done by making the car missfire (by pulling a coil) which allows a particular adaptation reset to be done. I'll report back on Sunday will further information on it if it works.

I decided not to fit NGK plugs as my local indy advised against it in the end. Instead i'm having a set of BMW oem plugs (not bosch ones') fitted on sat before the resets are done to ensure its definatley not a plug issue.

[DFWBMW]

Surprisingly nobody has mentioned anything about valvetronic

The geometry on the these units needs to be "perfect" for the car to idle and run smoothly, before doing anything your valvetronic adaptations need to be cleared and data for this needs to be analyzed. Just a heads up before you go chasing your tail :]

[bavaddict]

Originally Posted by 335i E92

Update...

The car went back a week after having the new injector and the plug was clear and clean so it looks like i had a leaking injector which was seperate to the rough idle issue.

I had master BMW tech look at my car and after a good hour or so of discussing how the rough idle started and what had allready been replaced he thinks a special reset needs to be done to help the adaptation of the new plugs.

This isn't a standrd reset and can only be done by making the car missfire (by pulling a coil) which allows a particular adaptation reset to be done. I'll report back on Sunday will further information on it if it works.

I decided not to fit NGK plugs as my local indy advised against it in the end. Instead i'm having a set of BMW oem plugs (not bosch ones') fitted on sat before the resets are done to ensure its definatley not a plug issue.

Thanks for keeping us updated on this. I have been watching other threads as well.

I am about to order the BMW plugs as well to see what happens.

Question is: how many ppl have ran into this issue with the BOSCH plugs? May be I need to start a thread on that topic alone.

Who knows if ECS Tuning may have the answer to this question, because I would think they will have to take the plugs back if thats the root cause, because there is no "Official" requirement for these adaptations reset as per Bentley or BMW.

[335i E92]

Originally Posted by bavaddict

Thanks for keeping us updated on this. I have been watching other threads as well.

I am about to order the BMW plugs as well to see what happens.

Question is: how many ppl have ran into this issue with the BOSCH plugs? May be I need to start a thread on that topic alone.

Who knows if ECS Tuning may have the answer to this question, because I would think they will have to take the plugs back if thats the root cause, because there is no "Official" requirement for these adaptations reset as per Bentley or BMW.

I hear what you're saying that officailly the adaptations don't need to be reset after a plug change but I know a few on here that have had this idle issue and have fixed it with mr5's BT cable fix.

The master tech is pretty confident that this reste along with a set of BMW eom plugs that have had there gap checked should fix the issue. If not I'm kinda stumped as everything else has been swapped out.

Saying that I'm in contact with another guy on here with our rough idle that has a tech raising a puma and going through the full monty sweep through the car. He's replaced everything that we have and is now looking in to a new DME.

Key is here is that we all keep coming back with updates and eventually we will find the answer between us.

[bavaddict]

UPDATE for those who are suffering from rough idle....last night I disconnected my battery left it disconnected over night and after few test runs it seems that idle is back to 600ish like it was before and motor does not seem to be "hiccuping" anymore.

Again I don't know if this is just co-incidence or not but seems to be working so far. YMMV.

If anyone else wants to give it a shot as well and update others that will be great!

[335i E92]

Originally Posted by bavaddict

UPDATE for those who are suffering from rough idle....last night I disconnected my battery left it disconnected over night and after few test runs it seems that idle is back to 600ish like it was before and motor does not seem to be "hiccuping" anymore.

Again I don't know if this is just co-incidence or not but seems to be working so far. YMMV.

If anyone else wants to give it a shot as well and update others that will be great!

Interesting!!

Glad it's seems to have worked, I might try this in a couple of weeks if my latest adaptation doesn't solve it for me.

Are there any dangers of disconnecting the battery? I'm running an Evolve flash, will this be wiped if the battery is pulled? Sounds great if the fix is that simple, just need to know more about any potential problems that come from cutting the power supply.

Anyone know much about this?

[335okc]

Originally Posted by 335i E92

Interesting!!

Glad it's seems to have worked, I might try this in a couple of weeks if my latest adaptation doesn't solve it for me.

Are there any dangers of disconnecting the battery? I'm running an Evolve flash, will this be wiped if the battery is pulled? Sounds great if the fix is that simple, just need to know more about any potential problems that come from cutting the power supply.

Anyone know much about this?

i dont have flash, so i cant say about that particular aspect. but i've left the batteries unhooked for 2 days before when i'm working on mods. no ill effect.
i think if you have an xi, you might get error.
fwiw, the flash should reside on the permanent storage part of the dme, *should* be ok.

[bavaddict]

Long term testing shows that my rough idle/misfires seems to have completely disappeared!

Did anyone else give this a shot?

[335i E92]

Originally Posted by bavaddict

Long term testing shows that my rough idle/misfires seems to have completely disappeared!

Did anyone else give this a shot?

Great to hear you found your fix... I'm going to try the battery disconnect tonight, will report back tomorrow.

Did you notice any other difference in how the car dirves or delivers the power? Just curious if the battery disconnect also resets the adaptations?

[BEAR-AvHistory]

Originally Posted by bavaddict

Curious if your plugs were geniune BMW or OEM Bosch?

OEM Bosch IIRC from Amazon......Has anyone tried the BSM socket, saw an add for $20

[Mike@N54Tuning.com]

FYI the BMS magnetic plug socket is back in stock and only $19. You won't have any issues with it.

[bavaddict]

Mike...curious is this M in C? or M in G or M in USA?

[raceyBMW]

Originally Posted by Mike@N54Tuning.com

FYI the BMS magnetic plug socket is back in stock and only $19. You won't have any issues with it.

I can vouch for this socket, works perfect, and the magnet is actually correct in this socket (i.e. no need to remove like the ECSTuning socket)....and the price is much better than the OEM one.

[AWD Addict]

Originally Posted by 335i E92

Great to hear you found your fix... I'm going to try the battery disconnect tonight, will report back tomorrow.

Did you notice any other difference in how the car dirves or delivers the power? Just curious if the battery disconnect also resets the adaptations?

Did you try the disconnect?

[rader1]

i was having severe misfires when running stage 2+ on the original(44K miles) plugs. Swapped them out with the autohausaz.com Bosh plugs and misfire was fixed and absolutely no problems with rough idle.

[335i E92]

Originally Posted by AWD Addict

Did you try the disconnect?

Disconnected battery over night with no resolve, also tried the full 'ECU reset' using the BT cable which didn't fix either.

I'm at the point of boredom with it now, car runs fine so i'm keeping an eye on here in hope that someone gets a fix.

[borisivan]

Originally Posted by bavaddict

Mike...curious is this M in C? or M in G or M in USA?

what about M in NH?