[bmwlover123]

Hello guys. I bought a 2007 e92 335i 10 months ago. I am having issues with it and can't decide between selling or repairing and keeping it. I definitely don't want to sell it but I dont know if the problem is too big. I was hoping my BMW brothers on this forum can help me identify the issue, so I dont get overcharged by the mechanics.

108,000 miles. It has never seen a mechanic since I bought(103k). I did an oil change but no maintenance other than that. When I was buying it, it had an "oil pan gasket leak", and I have been filling oil every 2 weeks since. I bought the car with this issue because it had 1 owner only and turbos were recently replaced. I finally have the money to get my baby fixed but I want to learn as much as possible before going to the mechanic.

The first issue is the oil pan gasket leak. But also sometimes smoke comes out of my exhausts, does this show that I'm possibly having another leak(walve cover gasket leak)? or the oil pan gasket leak can also cause the white smoke and the smell? I realized that the smoke reduced dramatically when I moved to a hot climate. It was happening much more in the cold.

Another issue with my car is, when I'm going with a steady speed over ~60 miles, the car kind of stutters for a split second, it feels like I removed my foot from the gas pedal for a split second.The rpm makes a really tiny move when this happens. It feels like the car wants me to go faster. Even when I put it in cruise control, same issue. However, it sometimes doesnt happen And this problem stops when I'm over ~100mph.

This stuttering things also happens when the car is in sport mode, and car is not speeding up. Like when I'm in sport mode and driving like a granddad, same thing is happening. It isnt really a problem when I'm driving fast in sport mode but if I'm trying to go with constant speed, this stutter happens like every 2 seconds. I recorded a video of the INPA live data when this issue is happening. I'm hoping pros on this forum can maybe find something out from this. In the video, the issue I'm talking about happens in these seconds: 7, 9-10, 14-15, 17

Video link:

Here are the error codes in INPA:


I really want to get my car fixed. I am going to move soon and the road is 2,000 miles. I dont want my car to break down on this trip so I want to fix as much things as I can at once. What are your recommendations on things I should replace? I dont know much about it but reading on the forums, I feel like replacing the injectors and spark plugs would be good. Also my car shifts well but not so smooth, BMW inspection record says that my transmission fluid is fine, but will replacing it make shifting smoother?

[Spyro235]

Replace your o2 sensors, precat at least, if not all of them. That was my stuttering problem. Replace them, and then either through MHD reset your adaptations, or find a real BMW shop that can.

[Milan]

I would this:

1) Valve cover gasket, PCV valve
2) Check and replace your vacuum lines with silicon

If you still have smoke it's your turbos. Hold off on the oil pan gasket until you know if it needs turbos because it's easy to get to while in there.

[bmwlover123]

Originally Posted by Spyro235

Replace your o2 sensors, precat at least, if not all of them. That was my stuttering problem. Replace them, and then either through MHD reset your adaptations, or find a real BMW shop that can.

Thanks for the advice. Was your stuttetering problem also making these kinds of engine sounds like in the video?

[marcvtec]

A stutter for 2 seconds., usually means detonation, Bad fuel?bad plugs?walnutblast valves?coils?
what octane are you running?
is the car stock ?
more info needed ?

[bmwlover123]

Originally Posted by marcvtec

A stutter for 2 seconds., usually means detonation, Bad fuel?bad plugs?walnutblast valves?coils?
what octane are you running?
is the car stock ?
more info needed ?

No the stutter is like 0.3 seconds. I always use highest grade fuel. Car is fully stock

[roadkillrob]

I would chase down the DME codes, the 2DED you probably have something using power like radar detector dash cam etc, any circuit tapped for power will throw that code, I get it from my dash cam.

The 29F4 29F5 or 02 codes, they show up if you have catless downpipes, but if you don't then that is probably the issue as it would indicate bad 02 sensors. Like Spyro235 said, replace the pre cat 02's or all 4 since you are high mileage and the generic Bosch ones are pretty cheap.

The pan gasket is what it is, needs replaced is a bit of work so a bit expensive. The smoke in the exhaust could be a few things, what color is it (white or black and does it hang in the air and have a smell to it?) Also may be an indicator of missing cat's with the codes as you get some smoke at startup and smell with no cats typically.

[bmwlover123]

Originally Posted by roadkillrob

I would chase down the DME codes, the 2DED you probably have something using power like radar detector dash cam etc, any circuit tapped for power will throw that code, I get it from my dash cam.

The 29F4 29F5 or 02 codes, they show up if you have catless downpipes, but if you don't then that is probably the issue as it would indicate bad 02 sensors. Like Spyro235 said, replace the pre cat 02's or all 4 since you are high mileage and the generic Bosch ones are pretty cheap.

The pan gasket is what it is, needs replaced is a bit of work so a bit expensive. The smoke in the exhaust could be a few things, what color is it (white or black and does it hang in the air and have a smell to it?) Also may be an indicator of missing cat's with the codes as you get some smoke at startup and smell with no cats typically.

Do you think the o2 sensor issue can cause the stutter? I realized that it only happens over 2000rpm. That is why it happens in sport mode and normal mode when going fast. Going with constant speed over 2000rpm causes the issue. Does this ring any bell to you guys?

The smoke has a smell to it and it definitely hangs in the air. I saw it not disappear many times in my rearview mirror. It is white smoke. Also when I push the car a little hard, it smells burnt oil when I park the car and get out of it.

[kenni243]

I can't tell much from the video clip... For white smoke/burnt oil smell definitely sound like valve cover. Pop it open and check the surrounding. Do you have any rough engine idle? The cause of stutter can be soo many things...

Bad O2 sensor
check - Coils/plugs if they are dry or wet.
Carbon build up (walnut blast required)
Leak Vacuum lines, boost solenoids

[bmwlover123]

Originally Posted by kenni243

I can't tell much from the video clip... For white smoke/burnt oil smell definitely sound like valve cover. Pop it open and check the surrounding. Do you have any rough engine idle? The cause of stutter can be soo many things...

Bad O2 sensor
check - Coils/plugs if they are dry or wet.
Carbon build up (walnut blast required)
Leak Vacuum lines, boost solenoids

I recorded videos of sensor and injector screens when this is happening. Can you please watch this and let me know if you can think of anything more specific?
Also I realized that it only happens over 2000rpm going steady.