[track370z]

Hi fellas,

I have been having a strange cold start issue the last week or so.

The only mod I have is a Kraftwerkes tune, which was fitted 3 months ago. Odometer is currently 90k

One morning when I started her up, very, very rough idle, and quite a lot of blue smoke from tail pipes, and a very strong smell of unburnt fuel. Threw CEL and carried on struggling to idle. A number of restarts didn't resolve the issue, so had to get to towed to a local indy in Melbourne.

Codes read were; misfire on cylinder 1 & 2, I believe HPFP code also thrown among several others. None were helpful in diagnosis as test were performed on HPFP which passed, smoke tested piping to flush out any air leaks passed, not throwing any faulty injector codes either. Best part is, while at the shop, the car just started running normally again without any intervention, and wouldn't repeat any of the symptoms.

Spark plugs are 30k old, all 6 ignition coils were replaced just prior to tune. Ruled out turbo seal, as failed turbo seal would not resolve itself, as blue smoke has completely disappeared.

The only symptom remaining now, is a 10 sec rough idle during cold starts which goes away.

I'm leaning towards leaking injector, which is dripping over night causing it stutter on initial start, but that doesn't explain why there was blue smoke initially.

Don't want to start replacing random parts, with out getting to the bottom of it, the indy is stumped, as am I.

Thanks in advance.

[drjekl]

Im no expert but sounds like a leaky injector to me:

- rough idle
- rough starting
- blowing smoke one start up (sometimes this can be mistaken for oil)

Having said that its difficult for us guys to diagnose just on the descriptions, it could be a multitude of things.

When you cranked the car did it start straight away, or did it wind over for a few seconds before starting?

I had misfire issues and my plugs were only a few months old, i swapped them anyway and bam it made a world of difference. If you're tuned plugs @ 30k kays old most likely need changing (N54's eat plugs) anyway, so perhaps $120 worth of plugs wouldnt hurt...

Since you're in melbourne take the car to jin @ Activemotorwerke and let the real experts diagnose the issue:

http://www.activemotorwerke.com.au/

[track370z]

Appreciate the response.

It did take slightly longer to crank, but I'm talking perhaps a second longer.

The only thing that has thrown me out was the blue smoke! Be it plugs or injectors, one would have expected black smoke - why blue? When the symptoms were present, the blue smoke was constant and rather heavy.

[BMWX5driver]

Blue smoke is the engine oil burning
Black smoke is result of the injectors leak
Also the injectors leak issue may happened on hot engine as well

[track370z]

UPDATE: Removed spark plugs to inspect, all sparks plugs are extremely black, except for one which was clean but very wet with fuel (2nd cylinder in from front of car).

Injector?

Time to visit Active Autowerke.

[drjekl]

Generally a wet plug is considered as a sign of a leaky injector...

Sounds like you could do with a set of fresh plugs, were the electrodes worn much at all (sometimes they don't appear worn until you compare them against a new plug!)

[track370z]

Active Autowerkes confirmed leaky injector this afternoon, should be good to collect later tomorrow. Plugs didn't look overly worn, seemed appropriate for the mileage.

Whilst it in the shop, will also get them to carry out the Alpina TCU flash! Any Aus members done this before? Thoughts?

[Digitalism]

Do it, also gets rid of the annoying Neutral Idle Control.

[Bbacho2002]

got all 6 bosch spark plugs / coils from under $200 usd if needed from partstrain.com if needed

[track370z]

Originally Posted by Digitalism

Do it, also gets rid of the annoying Neutral Idle Control.

What exactly does the "Neutral idle control" do?

[drjekl]

Originally Posted by Bbacho2002

got all 6 bosch spark plugs / coils from under $200 usd if needed from partstrain.com if needed

6 x bosch plugs and 6 x bosch coils for under $200? Really?

[Michael BD]

Originally Posted by drjekl

6 x bosch plugs and 6 x bosch coils for under $200? Really?

How often should these be changed?

[DR-JEKL]

Originally Posted by bornadog335i

How often should these be changed?

If you're tuned it's good to replace plugs every 2 years or so or around 30k kays. If you have misfires this seems to be one of the main culprits (along with coils)

As for coils I would guesstimate around 4 years or 60k kays... (once again with plugs these are the main culprits for misfire issues)

[pulsk001]

hi there, if you dont mind me asking, how much does it cost to replace the leaky injector and how big a job is it?

Do you just replace one or all 6?

I have a 335, same year and similar mileage, just getting prepared.

cheers
Sashi

[drjekl]

Originally Posted by pulsk001

hi there, if you dont mind me asking, how much does it cost to replace the leaky injector and how big a job is it?

Do you just replace one or all 6?

I have a 335, same year and similar mileage, just getting prepared.

cheers
Sashi

Generally injectors are best replaced per bank of 3 injectors (it's possible to just replace 1 injector if its faulty but if the others are of a similar age its only a matter of time before they fail so its best to replace the others whilst you're there)

By memory they are around $500 ish for 3 injectors, plus installation and coding on top of that.

Also BMW have released various revision of their injectors due to ongoing issues, so if you're going to replace them i would recommend doing all 6 at once with the latest part #.

So budget around $1500 for all six injectors...

[Pat335i]

Could this be the same issue happening on my 2009 335? Just picked it up (CPO) and every morning on start up she blows black smoke for a second. You're all suggesting a leaky injector?