Misfire & smoke on the exhaust side
 

This morning engine had trouble starting up and I could feel that some cylinders were not firing. I went on to drop of my kid to a daycare 5 minutes away and deal with it later. On one of the traffic signals I noticed smoke coming from under the hood so I pulled over and popped the hood open. Engine was still running erratically and at the same time there was white smoke coming out from the engine right side (where the exhaust is). I believe it was burnt oil judging from the smell. I dropped off my son, and decided to find the closest shop that can check it out, but after starting the car it was again running smoothly like nothing happened. No smoke either.

I also wanted to mention the high oil consumption but reading through other threads it appears it is "normal". It is worth mentioning that we finally has some decent rainfall overnight. Car is on covered parking but I am thinking that the moisture might have caused an electrical issue and misfire. I will check spark plugs and wiring, but what is puzzling me is the smoke coming out from the exhaust side.

CCV was replaced 2 years ago but I think i will give that CCV mod that seems popular a chance:

https://xoutpost.com/bmw-sav-forums/...-problems.html

Any thoughts about this? Where is the smoke coming from and would clogged CCV cause this? I suspect it would be smoking from the other side of engine if that was the case. Why did it go away just by itself, or was it just a symptom of misfiring cylinders? Any comment is welcome, I would like to keep it on the road for another year if possible. :)

It is a 3.0i engine with 250000 km on the clock.

Thanks!

We just had a thread about this exact problem. Check out "oil leak on a cold day" :)

He lives in KUWAIT. Doesn't get cold there. The low temp was 18C (58F to you people not on the Metric System) last night.

Get the X scan and see if you have any shadow trouble code(s) that haven't set off a DTC light. The fact that the misfire went away after a restart leads me to believe you had a misfire with fuel cutoff.

It actually does get cold here for a few weeks between December and January, much to the surprise of n00bs, but that period has passed as you have already determined. :)

However the symptoms do match what 80stech has described in the other thread...maybe something else messed up the CCV.

At the end this is all moot now as on the way back to work my X5 decided to commit suicide. Since the engine didn't cut it, it decided to pee the transmission oil and left me stranded on the side of the road. Quite interesting as the two problems can't really be related, can they? Also, the transmission oil lines have been replaced few months ago. :)

In any case, this did it for me, it is going to the recycler.

My Condolences.

Part it out.

I normally would, but dealing with potential buyers in Kuwait brings a whole new level of pain. Also, most of it is in bad shape, but I did put in a new alternator last year, that's probably the most valuable thing in there. Oh, and transmission was rebuilt three years back. I think I just want to get rid of it, owning it felt like having a child with special needs. :)

Also, this thing with the leaking transmission lines...it has happened for the fourth time in th last three years. First three times I have repaired the existing lines and then finally got a pair of brand new ones last summer and again they gave up. Makes me suspect there is something at play here, maybe a clogged cooling unit causing a pressure buildup (don't know if it makes sense?). What might cause the oil lines to give up so frequently?

That is strange about the cooler lines, looking at the original cooler lines I would say that the cooler itself would rupture before the lines would. Maybe lines where getting excessively hot though? Many of these vehicles have had the transmission over temp uncoded because of false reports from the sensor so maybe yours actually was over heating.