[x800pro6]

guies this is driving me insane!!

CAR:08 335i AT

car only missfires the next morning after the car has been driven hard the day before. i have swaped plugs, chnaged coil packs, the missfire smells bad, dumps a whole lot of unburnt fuel out of exaust.

new coil packs seem to have fixed HI boost full throttle missfire.

NOTES ABOUT MISSFIRE

* engine cooling fan goes full blast
*strange hi pitch tinging noise along with
* always same cylinders 2& 3 missfire.
* bad unburnt fuel smell
* missfire goes away and usually fixes itself after about 7 up to 12 times of starting let engine sit and restart. problem goes away like nothing ever happened..?
*miss only happens next day if i have been driving car HARD night before. e.g every saturday if i have been driving the car HARD on friday. so saturday morning its bad.


WHEN problem started:
problem started when i peformed 15ohm mod on my JB4 G4 and a piece of contact has come off(possibly damaging DME??). right now im on the jb4 G5 (still no fix)


my suspision:
i suspect it might be electrical like bad DME caused by my dodgy jb4 15k solder ? why does engine fan go full blast? thats normally related to water pump not working.

if it was fuel pump on injectors related would it not be missfiring all the time? and not just some times on cold starts.
also car starts straight, car does not take time to crank to start. starts straight away. so no long cranks.

i will get some fresh logs and repost

any help will be greatly appreciated!!

[x800pro6]

Just got some fresh codes:

29F1 Fuel pressure, plausibility
29CF Misfirings, cylinder 3



normally there is a few more codes.

[jdbretz]

What year is the car? You may have leaky injectors causing the issues. The fan may be some other unrelated problem, or just a byproduct of the car going into limp mode due to the misfires. Maybe you could pull the spark plugs on the cylinders misfiring and see how they look compared to the other cylinders. That may shed a little more light on the issue. Good luck

EDIT: I see its an '08. There is a recall for the injectors, so that leads me to believe even more so that they are your problem. I am not sure if the recall is available in Australia, but in the US you could get them replaced for free.

[x800pro6]

i have asked bmw about my injector recall , i gave them my vin number and said my car does not need the recall.

i did another start, codes:
29F1 Fuel pressure, plausibility
29CF Misfirings, cylinder 3
29CE Misfirings, cylinder 2

now the missfire is not going away! i took out the plugs two weeks ago, they all looked fine. i swaped them. still cyl 2 and 3

im going insane i swear!

[x800pro6]

its only certain batch of injectors in the recall program

[x800pro6]

when missfiring goes away engine fan does not go full blast! thats what makes me belive engine fan is related to the missfiring. maby as you said limp mode makes fan go full blast....

[jdbretz]

What is the build date on your car? I would try removing the JB4 just to confirm it isn't causing the issue somehow.

[danniexi]

leaky injectors. I ignored the problem for a while. Eventually the injector was stuck open and dumping fuel into the car. Smoke was coming out of the exhaust, misfires on all cylinders, and a horrible fuel smell permeated in the car. It was undriveable and I had to get it towed.

I had all six injectors and spark plugs replaced. Car runs smoothly with no issues, ESPECIALLY during cold starts. I had the same codes as you had as well, including the 29F1 and misfires in multiple cylinders.

As for the fan, I'd suggest looking into getting the water pump and thermostat replaced. I randomly got a 2EE6 code. After getting my car replaced with injectors, my water pump failed. I had the car towed AGAIN to get those replaced.

Overall, get those parts replaced as soon as possible. Yes it'll be expensive, but it's better than having your car towed before its too late.

[x800pro6]

im loving the feedback!! hank you to anyone who can help.


OKAY update: i have taken spark plugs out and cylinder 2 and 3 is covered in OIL ??? headgasket ? i have cleaned spark plugs put them back and now car runs fine!! im so confused, i think its headgasket? does oil line run close to spark plugs?

this happened before i cleaned all plugs and worked and car pulled strong.

[sammy_0559]

Originally Posted by x800pro6

im loving the feedback!! hank you to anyone who can help.


OKAY update: i have taken spark plugs out and cylinder 2 and 3 is covered in OIL ??? headgasket ? i have cleaned spark plugs put them back and now car runs fine!! im so confused, i think its headgasket? does oil line run close to spark plugs?

this happened before i cleaned all plugs and worked and car pulled strong.

Valve cover gasket.. Just do general tune up to your car it will run perfect.
1. ignition coils
2. Injectors
3. Plugs
4 Wanlut shell blasting intake valves.
5. Valve cover gasket. in your case.

i did all that about 5k miles ago.

[x800pro6]

thank you, what do i do? do i get a new seal or do i just tighten and tourqe up the bolts?

thank you for help!!

[Leekay07]

I have the same issue on my 08. Its at the dealer and has been since Wednesday. We already know what the issue is but they don't have the equipment yet to clean the Air Intake Valves. mine has 140,000 on it and never had intake valves cleaned.

[Leekay07]

I forgot to add. My car was rough starting. I had them change the plugs and not diagnose my car but they still did it. Told me i needed new valve cover gaskets and 3 injectors. Replaced them and the car still runs like crap so took it to my local dealer where it had a new coil pack replaced (for nothing) since then the cars been in the dealership because they dont have a walnut blasting machine to clean the intake valves.

[benzy89]

Originally Posted by jdbretz

EDIT: I see its an '08. There is a recall for the injectors, so that leads me to believe even more so that they are your problem.

Do you have any more info (or the link) about the injector recall? Thanks in advance.

[Leekay07]

It was done at the same time as the HPFP. I have never seen the actual numbers on the recall.

[x800pro6]

call BMW and give them the last 7 dig of vin number. they will tell you if your injector has to be replaced or not under recall.

im going to do the rocker cover valve cover gasket myself.

* im sure you can clean the vales yourself with a tooth brush and some brake fluid?




some notes

* water coolant feels slightly oily ( possible head gasket) however no white cream inside.

* oil is leaking in my engine however i can find where oil is comming from. i assume its comming from rockercover valve gasket. (i just hope my missfire is not because of a main cylinderhead gasket)

* sprak plugs conitain a lot of oil when removed thats why it has seriouse missfire on cold start. oil sits overnight and coats spark plugs. stopping spark!!

has anyone herd stories of head gaskets going on N54 ??

my dialema is cylinderhead gasket or valve cover gasket?

damm BM troubleu

[x800pro6]

i do notice more lag! possiby a slight power decrease. is there any possible way to remove injectors just for inspection?

[x800pro6]

nope sorry my injectors arn't part of recall i have already got that cheaked out. it already had update injectors. if they need replacing i have to do it out of pocket

[Leekay07]

remove the plastic Valve cover off the car takes 20mins. Then remove the coil packs and look for oil running down the wall with the sparkplug in. Then look around the valve cover.

Iwould just remove the manifold intake and check on the valves I bet they are nice and sludge.. the colder the weather gets the crappier the car runs.

[jdbretz]

Originally Posted by benzy89

Do you have any more info (or the link) about the injector recall? Thanks in advance.

Benzy,
Attached is SIB 13 14 10. It covers the injector recall for certain '07-08 model N54s.

OP,
What is the build date on your car? I know you said you called the BMW told you that you're not covered under the recall, but possibly they made a mistake. Knowing the build date on your car will confirm this quickly.

To clean the valves, you'll need a metal brush (i.e from a rifle cleaning kit) and lots of brake cleaner. The carbon will be caked on pretty bad and will require a lot of scrubbing to get it off. You'll also need a shopvac or some way of removing the excess brake cleaner from the valve ports. When/if you go to do it, just make sure the valves are fully closed before you get started. When I cleaned mine, I was able to clean 4 sets of the valves at once before I had to move the crank to close the other 2. There is a great DIY here on the forum.

I doubt its the head gasket, although I guess it could be possible. I would think you would notice discoloration of the coolant as well as sweet smelling white smoke from the exhaust. A leaking valve cover gaskets won't leak oil into the cylinder as far as I know. It will leak on the outside of the block which runs down into where the plugs go making the threads appear oily, but I don't think it makes it into the cylinder (although I could be wrong). Could you take pictures of the cylinder 2/3 plugs next to the other plugs? You are certain there is oil on them and not unburnt fuel?

Hopefully you get it sorted out soon, but it still kinda seems to me like a leaking injector still. What are the part numbers of your injectors?

[x800pro6]

i will get the part numbers. much appreciated for everyoes help guies!!.

okay verdict. too much positive crank case pressure. blowing too much oil out of valve cover gasket into spark plugs. the day after thrashing the car it missfires on cold start in the morning. everytime i clean all sparkplugs it runs awsome! definatly the oil on the plugs and coils guies!! maby my PVC valve is shot and not leting crank case pressure as it should? as i havent noticed too much oil in my OCC. its bmw's crappy design that the bolts are made out of aluminium that snap if you overtighten on the valve cover. i already snaped one. i drilled it out and tapped another thread. seems todays cars are made disposable.

note* if you drive car sensibly then the next day it does not missfire. only when its been thrashed and oil leaks and goes all over spark plugs, coils, etc

[x800pro6]

i will get the part numbers. much appreciated for everyoes help guies!!.

okay verdict. too much positive crank case pressure. blowing too much oil out of valve cover gasket into spark plugs. the day after thrashing the car it missfires on cold start in the morning. everytime i clean all sparkplugs it runs awsome! definatly the oil on the plugs and coils guies!! maby my PVC valve is shot and not enting crank case pressure as it should? as i havent noticed too much oil in my OCC. its bmw's crappy design that the bolts are made out of aluminium that snap if you overtighten on the valve cover. i already snaped one. i drilled it out and tapped another thread. seems todays cars are made disposable.

note* if you drive car sensibly then the next day it does not missfire. only when its been thrashed and oil leaks and goes all over spark plugs, coils, etc