[Cubieman]

I bought a pretty rough E92 that generally smells of buring oil while driving and will smoke out the tailpipes sometimes. I've got 180 psi across all cylinders fwiw and keep getting 2+ ozs of water in my low side catch can after maybe 50miles of driving which is odd.

Vehicle otherwise seems fine, no codes, no misfires etc., it's got all the standard FBO stuff and the PO installed brand new Dorman brand (I know) turbos 1 month before I purchased the vehicle.

I am looking to solve the smoking issue but first wanted to blast the intake valves. I found lots of oil in the intact tract, intercooler, chargepipe, intake etc.

My intake valves are absolutely coated in oil and presumably carbon as well. I held off on blasting for fear of the walnut media simply sticking to the oil/mucky valves and not being able to be vacuumed out.

Are my fears unfounded or should I try to get the caked oil out off the valves somehow before proceeding with a walnut blast?

Thanks, I am an S54 owner but this is my first turbo car as well as my first car with some potentially large issues and I am a bit overwhelmed.

[Jaronbwall]

That's a completely normal level of carbon build up. Hell my car was worse than that before I had the intake blasted.
As far as the smoke issue out the tail pipe. Seems like you have another issue. I was going to say turbo seals but you stated they're brand new. I'm not going to discount those turbos; never heard of them but I doubt it's your issue. I'd start investigating the injectors, plugs, and coils. See what index you're running. I'm running a mixed set of index 9 and 10 with no issues (knock on wood). Not much else causes smoke out the exhaust.
Don't look up the prices for new index 12... you'll cry.

[Cubieman]

Originally Posted by Jaronbwall

That's a completely normal level of carbon build up. Hell my car was worse than that before I had the intake blasted.
As far as the smoke issue out the tail pipe. Seems like you have another issue. I was going to say turbo seals but you stated they're brand new. I'm not going to discount those turbos; never heard of them but I doubt it's your issue. I'd start investigating the injectors, plugs, and coils. See what index you're running. I'm running a mixed set of index 9 and 10 with no issues (knock on wood). Not much else causes smoke out the exhaust.
Don't look up the prices for new index 12... you'll cry.

Thanks, I've got Index 11 that were cleaned/flow tested etc., and the coils are Bosch manufactured in 2018. Probably time for new plugs from the looks of it.

I do need to check if the PO coded the injectors though.


So a bad PCV system (VC) couldn't cause smoke from the tailpipe? Besides a HG or Turbo seal what other things should I look for at for smoking from the tailpipe?
Thanks!

On a side note the valves cleaned up relatively well, I did more work by hand with a pick than the cheap ass HF blaster was able to deal with.

[Info@mad-us.com]

If they are using a quality walnut blaster tool it shouldn't be an issue.

[Cubieman]

On a side note, why would the entire intake system be coated with oil other than turbo seals? Valve seals?

I have white smoke as well out the tailpipe sometimes at a stop and persistent smell of burning oil. I do see that the rear turbo drain line connection at the turbo is wet with oil so that could definitely account for the oil smell but it would seem there are many factors to cause a smoking exhaust as I have read.

Don't want to throw parts at it, would like to diag as much as possible here.

I am just not familiar with turbo engines yet.

Id. 11 injectors, VTT PCV, Low side OCC, 180psi across all cylinders.

I accumulate 2+ ozs of clear water in my catch can after only 50 miles of mild city driving and do not seem to be losing any coolant. Nor do I see signs of water in my oil or vice versa.

[Jaronbwall]

PCV valve! ahh damn I forgot about that. YES replace that part. They sell upgraded ones made out of billet aluminum. It's cheap insurance and those fail over time. That could be failing on you. The intake side does get oily over time but it shouldn't be "dumping" oil out of the piping if you take it apart. Hopefully it's not that bad. My 335i never had that issue and I'm FBO stage 2+.

If you're running a tune the oil build up will be worse which is why people install the catch cans. I completed a ton of maintenance before going FBO. What other maintenance have you completed?
Could this be an OFH gasket leak? Maybe the vanos sensors need replaced? My VCG was leaking and dripping onto the down pipes causing white smoke at stoplights. Talk about a scary experience. I thought my engine had caught fire.
This forum is critical to get the information you need.

[Cubieman]

I have no visible leaks at my VC or OFHG but I bought a new VC/VCG kit as well as OFHG/Thermostat gaskets and will be seeing if those items help any, wishful thinking possibly..

[Jklad]

Originally Posted by Cubieman

I have no visible leaks at my VC or OFHG but I bought a new VC/VCG kit as well as OFHG/Thermostat gaskets and will be seeing if those items help any, wishful thinking possibly..

I would first replace the pcv valve with an upgraded rb pcv. Also, replace the pcv hose at the rear of the valve cover (the hose with the built in flapper) and see if those two things cure your smoke. You want to replace both those parts anyways if you're replacing the entire valve cover. And don't cheap out with an aftermarket cover, they have had many documented problems over the years. Go with the oem valve cover kit, which includes a new cover, new gasket, and all new bolts which you will need as well. Replace the plastic junk pcv valve on the cover with the upgraded version from Rb.

This is also a great time to replace all your vacuum lines, so have at it.

[Cubieman]

I did kind of cheap out with the elring VCG kit for $350 vs. ~$500 OEM BMW so hopefully that was not a big mistake just to save $150.

I already have a Vargas PCV valve, unless the RB has some advantage I'll probably just continue to run that.

Still deciding whether or not to keep this vehicle, just need it to quit smoking. My main ride is an E46 M3 so I'm trying not to throw too much money at the 335, seems like that is all one does with these N54's..

[jadams161]

You should do some research and learn about the N54 engines. They have oil blow by and are direct injected. This causes oil to build up in the intercooler, charge pipe, intake and intake valves. You need to install an oil catch can and clean the entire intake tract. Walnut blasting is very simple and has to be done on direct injected engines. Harbour Freight has a good system for it. Spark plugs and coil change after cleaning is a good idea and normal maintenance.

[Wes335XI]

Originally Posted by Cubieman

I did kind of cheap out with the elring VCG kit for $350 vs. ~$500 OEM BMW so hopefully that was not a big mistake just to save $150.

I already have a Vargas PCV valve, unless the RB has some advantage I'll probably just continue to run that.

Still deciding whether or not to keep this vehicle, just need it to quit smoking. My main ride is an E46 M3 so I'm trying not to throw too much money at the 335, seems like that is all one does with these N54's..

I've done the same as you, throwing money at my N54 trying to fix a smoking issue. New rebuilt turbos, External PCV Valve, lightly used Index 12 Injectors, New boost solenoids, new vanos solenoids, even walnut blasted twice, once at 50K miles, another at 90K miles... Still smoking.

Low and behold, my issue may end up being the Valve Stem Seals, which makes perfect sense once you understand how those work. If your car is only smoking after idling for a while or after sitting at a stop light then clears briefly while going down the road, it is most likely Valve Stem Seals. Once I confirm 100% that is the issue and it fixes my smoking issue, I am going to do a long writeup about it. Too many people point to turbo seals, injectors, HPFP, etc, but when do you ever hear about Valve Stem Seals?

It's been extremely frustrating, but I'm happy to have finally found a mechanic that may have solved my issue for good and I can finally enjoy my car again.

[Mustafa.e92]

Originally Posted by Wes335XI

I've done the same as you, throwing money at my N54 trying to fix a smoking issue. New rebuilt turbos, External PCV Valve, lightly used Index 12 Injectors, New boost solenoids, new vanos solenoids, even walnut blasted twice, once at 50K miles, another at 90K miles... Still smoking.

Low and behold, my issue may end up being the Valve Seals, which makes perfect sense once you understand how those work. If your car is only smoking after idling for a while or after sitting at a stop light then clears briefly while going down the road, it is most likely Valve Seals. Once I confirm 100% that is the issue and it fixes my smoking issue, I am going to do a long writeup about it. Too many people point to turbo seals, injectors, HPFP, etc, but when do you ever hear about Valve Seals?

It's been extremely frustrating, but I'm happy to have finally found a mechanic that may have solved my issue for good and I can finally enjoy my car again.

think my valve stem seals are letting some oil by occasionally too. At first I thought it was the stock turbos which it mostly was but I still get a puff of smoke here and their. Low speeds like driving through the drive thru and after running the car hard on the next restart it will let out of a puff

[Cubieman]

Can we do valve stem seals using the compressed air method on our N54's?

[Jaronbwall]

Originally Posted by Cubieman

Can we do valve stem seals using the compressed air method on our N54's?

DIY valve stem seal replacement sounds scary to me but maybe it's not terrible... I've never heard about that issue. Hopefully you don't need it.

[whyzee125]

My money is on a bad PCV causing the smoke. The only things that really cause that on these engines usually are bad turbos and bad PCV. It's possible it's bad valve stem seals too but that's not a common issue at all. Good luck!

[Cubieman]

Thanks guys, just wrapping up new VC/VCG, OFHG/Oil cooler gasket, flapper valve, RB PCV.

I had a TON of milkshake oil in my flapper valve and tubing going to the low side OCC, if I haven't already mentioned I get about 2oz of clear water inside my OCC about every 50 miles w/ no notable losses of coolant from my res. and good 175/180 compression #'s.

I have a feeling all the work I just did was worthlessness as all the aforementioned gaskets I replaced were in immaculate condition and the VC itself was extremely clean with no plugged up PCV ports etc.

Looks like the PO did this work in the recent past possibly trying to address the same issues.

He put brand new Dorman turbos on, they haven't been run for more than 400miles but I'll have to pull the DP's next.

Was going to sell this car but I am starting to like it even though compared to my S54 it seems like it has so many potential issues, not to mention $2600 fuel injectors, my god..

[Quick335XI]

Is walnut blasting still important when running E85?

[Cubieman]

Originally Posted by Quick335XI

Is walnut blasting still important when running E85?

Type of fuel won't make a difference, port injection would make a difference.

It's not the fuel, it's where the fuel is (or isn't in this case) sprayed that allows these deposits to build up.

[Quick335XI]

Originally Posted by Cubieman

Type of fuel won't make a difference, port injection would make a difference.

It's not the fuel, it's where the fuel is (or isn't in this case) sprayed that allows these deposits to build up.

I have PI; are you saying I don't need to worry as often about walnut blasting?

[Cubieman]

Originally Posted by Quick335XI

I have PI; are you saying I don't need to worry as often about walnut blasting?

I would say if you have PI your walnut blasting intervals would be longer, I don't consider myself an expert but in a non DI car walnut blasting isn't a thing.

Now, there are of course variables such as how much fuel is dispensed via PI and how well the spray of fuel cleans the valves compared to an engine designed with port injection from the factory. In my mind you could probably at least double your intervals, I would like to hear what others think on this.