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Discussion Starter #1
Upon changing my oil last night, i realized that it had the smell of gasoline in it...it wasnt too overpowering but it was definately there. Is it normal to smell gasoline in the oil or is that bad?
 

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Good question. I noticed that in my Camaro. I took out the dipstick just to check the level and consistancy since I don't use it often and something made me smell it...and it definitely had an odor of gasoline. The next time the oil is changed we'll see if there is in fact gasoline in there. I have not smelled the GTO oil though.

I don't know how true this is, but a friend of mine told me that it should just burn up while the engine is running and may not cause harm (of course in a limited amount). However, I am at least concerned...they shouldn't be mixing.

Does anyone have any feedback on this? What can cause it and what are the risks?
 

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Why would the oil smell like gasoline?

If you run the car in cold weather, the fuel mixture is richened to warm engine, excess fuel not burned can get into the oil. Also, if you have a car that starts hard-long cranking or has a misfire; the excess gas that is not burned will get into your oil.



Your engine has been severely flooded or, if your car has a carburator, the float needle seat is shot. Whenever your oil smells like gasoline it's very bad for your engine. Change the oil ASAP.



Your engine maybe tired. you have what is called blow-by. Your piston rings are not sealing on the cylinder wall. If you watch you may be using oil also.


Many things can cause this, some are, from a short driving cycle that doesn't allow the engine to fully warm up, to a faulty fuel pressure regulator, to leaking fuel injector/s or a carburetor float bowl being overfilled, to worn engine parts, like piston rings, valve guides, faulty spark plugs resulting in poor fuel burn ect, ect.

Basically it's gasoline getting from the top of the engine, into the bottom of the engine, where the oil sump is.

Gasoline in the oil isn't good for it, or the engine, as it dilutes the oil & robs it of it's lubricating properties, resulting in accelerated engine wear & bad engine deposits.

Best to change the oil & filter right away, review all the listed ideas & have the most likely checked out by a pro you trust.

If your cars mechanical condition is ok, but your driving cycle is short, after changing the oil & filter, try changing your driving cycle, or by taking your car on a weekly 20 mile interstate round trip, to warm the engine & oil up completely, to evaporate condensation & any gasoline thats found it's way into the crankcase oil sump.
 

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Discussion Starter #4
I am not burning oil and I check at every fill up and the level is always the same. Spark plugs and cold whether are the more likely, and more favorable, possibility for me. I may even attribute some of that smell to the Zmax oil additive I put in the car. I did notice a power difference when I switched to RP. I now chirp third and spin second for a longer period of time than I did before. That brings up the issue of finding the right plugs to put in her. I will begin looking into it and smelling my oil more often. Sounds rediculous but its necessary. Ill post anything I come up with
 

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Thanks for the wealth of info Judge!

The Camaro I have will be turning 22 years old soon and on the original motor. I don't use it too often and in the winter I just start it up, warm up (carbed) and roll it around the driveway just to get all the fluids moving every couple of weeks or so. I never have to add oil and it doesn't smoke when running (except the first few seconds of start up - typical with these cars). I guess in my case it can be any of the problems that you have mentioned. I can't wait to get the engine and tranny rebuilt with some added goodies to what I already have...but who has money for that :( She's still running great though which is all I can ask for at this point. Never had a major issue besides typical maintenance and repairs over the years.

Thanks again.
 

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Discussion Starter #6
Went to the dealer today and told them about the problem. My new oil has 700 miles on it and it has the gasoline smell too now. The dealer told me a gasoline smell is normal. I checked the oil on my moms 05 volvo and I could smell gasoline in its oil as well. Im confused now
 

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With the exceptions in the Q&A article I don't buy it. It's not normal to have anti-freeze, or ATF mixing in with the oil either. All the articles on this matter I have read state its not normal to have gas mixing in with the oil. I've been changing oil in my cars since 1976 and never have I ever had a gas smell in used oil or a "slick" atop of the oil related to gas.

Maybe someone can produce an article from a reputable source stating gas and oil mixing in the crank case is normal and no harm will result as a result of this?
 

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With the exceptions in the Q&A article I don't buy it. It's not normal to have anti-freeze, or ATF mixing in with the oil either. All the articles on this matter I have read state its not normal to have gas mixing in with the oil. I've been changing oil in my cars since 1976 and never have I ever had a gas smell in used oil or a "slick" atop of the oil.

Maybe someone can produce an article from a reputable source stating gas and oil mixing in the crank case is normal and no harm will result as a result of this?
If that's the case I guess all of my vehicles have been malfunctioning because the oil has always smelled like fuel was in it. Even the one that got 200,000+ miles (1988 Chevy Beretta) on it's engine (2.8 liter V6) before it died due to neglect. Or maybe it's just that the oil as it gets contaminated smells like fuel is in it when it really isn't which could be the case. Eric, let us know what is said about the smell of fuel in the oil on your mom's Volvo if you guys decide to take it in. I don't have a definitive answer or fact but I say that it's highly possible for a very small amount of fuel to get by the piston rings when the engine is cold and first started. Remember, our cars run pig rich from the factory so that could aid in the problem too. Maybe I'm wrong but that's just my opinion.

This same question was asked here too:
LS1GTO.com Forums - Quick Dumb Question Fuel Smell in Oil

Check out post #8. Seems to be the same thing I was stating.

Changed the oil this morning, and it smelled like gasoline. - Corvette Forum

I'd say this is nothing to worry about. It means your car went too long on that oil. Basically when your car is cold, you hear piston slap, because the hypereuetic pistons are expanding with the heat and eventually grab the cylinder walls tighter and seal up. On alot of cold starts, you will get slight blow-by on the cylinder walls letting the atomized fuel seep past the rings and get into the crank case. Enough time and eventually your oil smells like gas. Bad thing about this is gas severely lowers the viscosity of your oil and makes it very watery and ineffective. 50% oil life left = 3000 miles, ignore what GM says, synthetic is great, but not 6,000 mile great... these are performance cars, and if you drive them like that, 3,000 is when you need to change your oil.

Now, if this is a higher mileage motor, this is not uncommon. If its a low mileage motor.. might be a concern.. either way if you have some free time and patience, do a leak down test and see yoru compression... this is normally a sign of blowby.
 

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Discussion Starter #12
Im still a little back and forth on this issue. I need to get it figured out though because I payed a pretty penny for the oil thats in there now and it doesnt even have 1000 miles on it. I will keep looking into it.
 

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ATF and coolant definitely not normal in the oil and something to worry about, not so much gas smell. I wouldn't be worried unless it smelled very diluted and you were able to light it on fire, :lol: especially after 700 miles.. Have you been engine braking a lot?

However,... that ls2 has higher compression, someone mentioned that they normally run richer, and more so in cold weather. Not to mention that your workin with a high performance beast, not a grocery getter volvo.

If you were getting a significant amount of blowby into the oil, then the engine would also be consuming a noticeable amount of oil. So, don't worry too much about it. Just keep smellin that ATF (if it's an A4).:cool
 

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I have never changed oil myself but i always stand right next to the person who does it. and have always looked around the engine and smell, Have never smelled Gasoline. And i am talking about a 96 Camry, Acura TL, 03 and 05 an Audi A4 and Corolla 05.
 

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I have never changed oil myself but i always stand right next to the person who does it. and have always looked around the engine and smell, Have never smelled Gasoline. And i am talking about a 96 Camry, Acura TL, 03 and 05 an Audi A4 and Corolla 05.
That's hard to believe. It is a major liability (insurance) issue to have a customer in a shop when work like draining the oil, since the car is usually on a lift, is being performed. Most shops have guard rails or a chain in place to keep unauthorized people from entering the work area.
 

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Discussion Starter #17
You wouldn't smell it that way either. I have to put my nose right up to it to smell the gasoline. Even when I drained it the first time I smelled gasoline on my hands and not from actually draining the car.
I have never changed oil myself but i always stand right next to the person who does it. and have always looked around the engine and smell, Have never smelled Gasoline. And i am talking about a 96 Camry, Acura TL, 03 and 05 an Audi A4 and Corolla 05.
 

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If the smell of gas on your hands from changing the oil is overpowering the smell of used oil, I maintain, its not normal.

Google up this subject and look for reputable feedback from people in this field and if you find any, post em up.
 

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Discussion Starter #19
I dont have it in print but a buddy of mine who is a mechanic/engineer on a racing team and has TONS of experience with performance vehicles and stock cars said its just a sign that the car is running rich. He said it is nothing to worry about. You guys dont know him but I know that if he says its okay...its okay
 

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I dont have it in print but a buddy of mine who is a mechanic/engineer on a racing team and has TONS of experience with performance vehicles and stock cars said its just a sign that the car is running rich. He said it is nothing to worry about. You guys dont know him but I know that if he says its okay...its okay
I believe him. Has your car ever been tuned?
 
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