Sweet-smelling white smoke, need advice.

[febul]

I purchased an 09' 135i with approximately 45k miles a few months ago. Only bolt-ons are catless BMS downpipes and Meisterschaft midpipes. Right before purchasing I found out that the previous owner had temporarily been running JB4 until he uninstalled it due to issues. Later, I also found out that he was in possession of a Cobb AP that he made no mention of. So I know he was running higher than stock levels of boost.

A few mornings ago I pulled my car out of my driveway and noticed an unusually large amount of sweet-smelling white smoke coming from my tailpipes. I recorded it immediately.

Video without revving:
https://www.dropbox.com/s/8qy2lkgcdz...72808.mp4?dl=0

Video with revving:
https://www.dropbox.com/s/2wzv8i80va...74632.mp4?dl=0

This wasn't the first time that I've noticed this, but there was never that much smoke.

I showed these videos to a friend who suspects a blown head gasket/cracked block.

I hadn't driven it since until today. It's still smoking, even when driven up to operating temperatures. The car also feels as if it's driving differently. I'm not sure if it's my paranoia or not, but it feels as I'm getting a lot less power than usual.

I don't know if it's related or not, but I noticed a small leak of what appears to be oil right by the turbos a few weeks ago. Here's a picture:

View post on imgur.com

I'm not sure what to do at this point. What steps can I take to identify the cause of the smoking and have it fixed?

[135Pats]

A few thoughts....

1. Both videos are the same! And in that video it looks rather moist and cool out - how much of that is condensation?
2. Is there any type of smell to what's coming out? Don't poke your head into the exhaust but see if you can catch a whiff when coming to a stop. If it smells sweet and syrupy, you are burning up coolant.
3. If need be pull the plugs, check them to see if they're fouled (oil could be slipping past a ring), and do a compression and/or leakdown test.
4. Are you bleeding boost? If so, you could be loosing it into the coolant system.
5. Are you loosing oil? Monitor oil levels. Do the same for coolant.
6. Pull codes


I'd be shocked if you cracked the block. And i'd be rather surprised if you smoked the head gasket, that's rather rare on these motors. FAR more likely is that with the removal of all 4 cats, the lack of backpressure is pulling oil out of the bearings and burning it up in the exhaust. Now THAT is pretty common.

[febul]

Originally Posted by 135Pats

A few thoughts....

1. Both videos are the same! And in that video it looks rather moist and cool out - how much of that is condensation?
2. Is there any type of smell to what's coming out? Don't poke your head into the exhaust but see if you can catch a whiff when coming to a stop. If it smells sweet and syrupy, you are burning up coolant.
3. If need be pull the plugs, check them to see if they're fouled (oil could be slipping past a ring), and do a compression and/or leakdown test.
4. Are you bleeding boost? If so, you could be loosing it into the coolant system.
5. Are you loosing oil? Monitor oil levels. Do the same for coolant.
6. Pull codes


I'd be shocked if you cracked the block. And i'd be rather surprised if you smoked the head gasket, that's rather rare on these motors. FAR more likely is that with the removal of all 4 cats, the lack of backpressure is pulling oil out of the bearings and burning it up in the exhaust. Now THAT is pretty common.

I just updated the thread with the fixed video link.

1. It was pretty cool out, but it was the sweet-smell and amount of smoke that caught my attention.

2. It was a rather sweet smell.

3. How would I go about performing the compression & leakdown tests? I don't mind going out and getting the required tools.

4. How could I tell whether or not I'm bleeding boost?

5. I checked my oil level last Sunday for this very reason. I'll be re-checking it tomorrow and reporting back. I have not checked my coolant level as yet, but will when I recheck the oil level.

6. About a month ago I had a SES light and brought it to a mechanic. We ran a scan and got these codes:

P2096 - post catalytic fuel trim system too lean. Bank 1
P2272 - o2 sensor signal stuck lean - bank 2 sensor 2
P2098 - post catalytic fuel trim. Bank 2
P0171 - system too lean bank 1
P0174 - system too lean bank 2

I made mention to him that the previous owner had installed the BMW DPFIX onto the ECU. He adjusted the dial on it and told me to clear the codes, which I did. After 300+ miles the codes have not returned. I'm worried that the codes are simply being hidden by the DPFIX.

I know that cracked blocks & blown head gaskets are rare on these cars. I've babied the car since I got it in July. But I have no idea of what boost levels were ran through it by the previous owner, or of how it was driven.

[135Pats]

Pull the DPfix first and foremost. It's going to mess with your trim control since it just pulls from a single exhaust bank. Not good.

I didn't pay attention to the obvious title in your first post lol. If it smells sweet, it's likely coolant. When the motor is cold take the expansion cap off and just see how much there is in there.

Any decent technician can do a compression test, you can do it yourself very easily as well once you've pulled the plugs. I'd recommend that as a next step. All of those lean codes worry me.

[febul]

Originally Posted by 135Pats

Pull the DPfix first and foremost. It's going to mess with your trim control since it just pulls from a single exhaust bank. Not good.

Can you explain what you mean by it messing with the trim control and it pulling from a single exhaust bank? I've tried to look up how the DPFIX works with no success.

Originally Posted by 135Pats

I didn't pay attention to the obvious title in your first post lol. If it smells sweet, it's likely coolant. When the motor is cold take the expansion cap off and just see how much there is in there.

I actually edited it after you replied, lol. Figured that it was a really important detail that I missed. I'll be checking the coolant level in the morning, I'll report back!

Originally Posted by 135Pats

Any decent technician can do a compression test, you can do it yourself very easily as well once you've pulled the plugs. I'd recommend that as a next step. All of those lean codes worry me.

I'll do the compression test myself. Is there anything that I need to disconnect before I do it? They worry me too, I hope I can get to the root of the issue quickly. Would you recommend me not driving the car?

[Solo_M_Tech]

Dude your burning coolant. Could be turbo seals, head gasket, a crack somewhere. It's probably seeping into a cylinder over night through a hairline crack. When you start it up it has to burn off the coolant in the cylinder. Since it's colder outside, the metal in the block could be contracting, making the crack bigger, and allowing more coolant into the cylinder. Hard to say where without a leak down test, and a coolant system pressure test. Any tech in almost any shop can do those test.

[JohnnyG_TO]

^^ What he said. Coolant burns white and it doesn't just smell sweet, it is sweet. That's why animals will lap it up (and then pay the price).