Tittle pretty much says it all, I was trying to diagnose why I was getting a weird sputtering issue while at higher RPM going up hill, typically going onto a freeway (gunning it pretty good). Well while I was looking in the engine bay to make sure nothing crazy was going on, mind you I know very little about cars but I know if something is leaking its bad and thats what I was checking for. Anyways, I checked my oil and noticed it smelled a little like gasoline. After some research on the web folks say I should be concerned if I see smoke coming out the tail pipes or if the inside of the car smells like gas, but it doesn't. My biggest concern is that my engine isn't getting the proper lubrication because the oil is diluted with gas. Second, I don't really know what is causing it.

Some info about the car...2012 CM S All4 50k miles, not sure if its ever had spark plugs replaced (should they be at 50k?). I have been told the plugs could be a cause for it if the vehicle isn't firing on each cylinder and not burning off the gas. I also HAD a JB+ mod installed and took it off to try and diagnose if that was the cause of my sputtering issue...not sure if having that installed caused it to run too rich or what. I installed it in May of this year and only really noticed the sputtering issue when it started to get cold in the last month or so. The only other thing I have done to the car is add JCW exhaust but I don't think that would do anything. I am in the middle of my oil change cycle and have 2500 miles left, to save my engine I will get a oil change but I just don't know if this is something common or even a problem in Mini's...

Another thing to add to my rambling, is that sputtering issue possibly related to why there is gas getting into my oil?

And just if it matters, I primarily drive in sport mode...because it sounds cooler...lol

Any help is very much appreciated!

 

Leaking injectors, weak spark are main culprits and yes, your engine will suffer from thin oil.

 

Gas in the oil is usually caused by blow by - common with turbo engines. This happens given the high pressures within the cylinder where gas makes it past the rings and mixes with the oil in the crankcase. This is why folks are talking about lots of smoke being the issue....

It's pretty common and not a real issue.

You might want to send a sample to blackstone and get a report...

That said, sputtering might come from worn out spark plugs/ plugs that aren't gapped optimally. Have they been changed?

 

Oil should not smell of gasoline, period. Blow by is a sign of worn rings. Fuel should be burnt in the chamber and none left to 'blow by' which would be burnt gases only and cause a rise in crank pressure, overfueling puts gas in oil which is outside normal operations. For me that would be a real issue.

 

I assume what you mean by overfueling is that too much gas is being put into the engine from the fuel injectors and not into the tank when I fill it up lol...I am an idiot when it comes to cars...

As far as I know, the spark plugs have never been changed. I got the car with 36k miles and its at 50k now. Is it time to change them? I don't remember seeing anything in the manual about service intervals like I have with other vehicles.

All this being said, what are my options? Can a shop/dealer quickly diagnose this without me spending an arm and a leg or will they have to tear it apart to see what the deal is? Should I just bring it in and they can smell the oil and tell if its something of concern? Should I get the oil changed immediately? Its more than likely a spark plug issue and not a fuel injector issue?


Thanks for the help/info!

 

I keep forgetting to confirm...can the JB+ mod be the culprit for this issue?

 

Interesting. Did you remove the jb+ and see how it runs? The jb+ is simply a plug in device that can be removed without any fanfare.

Yes, I would replace the plugs - or at least check the tips. I think it's possible you will find that they have deteriorated.

As for the blow by, I am simply going on years and years of experience with forced induction engines. It is what it is and it starts very early on in the life of the engine. It is VERY common. You ought to smell the oil that I drain from my 15K mi F150 ecoboost. LOL

I would again recommend getting a blackstone report done... It is a relatively inexpensive way of understanding what is going on with your engine.