Gas fumes in my oil?
 

Seems that I've got a strong odor of gasoline in my oil. This doesn't sound like a good thing to me. Can someone give me your opinion of exactly how bad this is?

96 E320 (W210) 149K miles

I can't tell you how bad it smells, but gasoline in oil is not a good thing to have. You probably have a leaky injector or your car is running way too rich. have you noticed black smoke coming out of the exhaust? Don't run the engine with too much gas in your oil. Very bad for the engine.
jaclD

The car seems to run fine. No skipping or noise, good power, and no smoke. I notice it when I check the oil. The oil color looks fine. I've had no check engine lights or anything.

Bad rings?
Bad Gaskets?
Leak somewhere else?

I believe it is a leaky injector, quite possibly at the seal.

BTW, gas has a strong odor, and it doesn't take much of it to permeate the air. I am currently replacing a leaky fuel hose that had a small leak, but it seemed as though the car was bathed in gasoline!

I suspect the management system is compensating for the added fuel, and that is why you don't notice any performance anomalies. If the leak gets any worse, the car will not be able to compensate beyond some parameter, and the O2 sensor will probably discover that first and light up the "Check Engine" indicator.

Note that gasoline washes the oil off the cylinder walls, effectively exposing the metal components to friction due to lack of lubrication. Translation: premature engine wear. :(

The excess fuel has to be dealt with at the exhaust end as well, and this will shorten the life of the catalytic converter.

Get those seals taken care of soon...

I don't understand how a leaky injector can get fuel into the engine block. Is fuel getting past the rings into the block during the exhaust stroke?

A leaky injector will drop raw fuel into the cylinder. If this raw fuel is not burned properly and does not go through the exhaust system, it ends-up in the oil pan. Raw gasoline will wash off all oil from the cylinder walls and dilute your engine oil. Thin baby oil is nor very good at lubricating the crasksaft/camshaft bearings, valve train and everything else inside the engine, thus, accelerated wear.
JackD

Do you let your car idle to "warm it up" before going out in the cold to drive it away? If so that will cause gasoline smelling oil. The engine warms up so slowly when idling that gas condenses on the cylinder walls and runs down past the rings, contaminating the oil (and washing the oil off the cylinder walls). I've had mechanics tell me they can tell whether a car sat and warmed up 10 minutes before being driven or not, based on the wear on the cylinder walls. Don't know whether I really believe it or not.

- Jim

On older CIS models, there is a vent from the pressure regulator to the breather hose. In the event of a diaphram leak, the gas will 'vent' to the crankcase. If your pressure regulator has such a connection, remove it to see if that is the source - carefully.

Steve

you can usally feel the difference if there's gas in your oil by pulling dip stick and rubbing the oil between your fore finger and thumb and smell it then try the same with a little of the brand of fresh oil that you use. If there's ever any gain on dip stick don't drive it, it dose not take much gas in oil to wipe out every bearing.........
William Rogers........

Update:

Spoke with Donnie at MBA, seemed to think the same things. Pressure Reg or injectors. Contacted Ken at Benz Store. He did some research and found that there have been reported problems with non-bosch pressure regs. He got me a part and printed out an illustration. Picked up the part and installed it in less than 3 minutes. Changed the oil and will check tonight if fumes are back.

so far, so good. I smell exhaust fumes only, which I'm not used to having diesels for so long.

I suppose this will help our fuel milage, too.