ok, i'm looking to purchase this car i don't think it matters what kind of car it is, but what i am concerned about is i took off the oil cap and there was a white milky residue in the oil cap, my first thought was someone used water to clean the oil cap or lack of oil change. Car has 40k on it, anyone have any ideas. i really need an input

 

What does the oil at the bottom of the dip stick look like? If the oil at the bottom of the engine looks normal I would guess that it's just condensation. I owned a vehicle (GMC) a few years back that had that same problem and it was due to condensation that would form under the oil cap. It didn't affect the engine or the oil as long as you did the regularly scheduled maintenance.

If the oil at the bottom of the dipstick looks the same as under the cap I would steer clear. That could possibly be a blown head gasket or crack in the water jacket.

 

teh oil @ dipstick look fine not milky but if i buy this thing i'll check it again, thanks for the input Friend

 

My dad's 98 neon had the same problem, it was mixing the engine coolant with the engine oil, bad sign, blown head gasket, it ran fine, but we got rid of it.

 

I would suggest checking out the PCV (positive crankcase ventilation) system, specifically the PCV valve to see that it is operational and that there are no kinks or obstructions in the vacuum lines. Aside from keeping fumes from escaping (for emissions control) it is supposed to evacuate any moisture from condensation when things come up to temperature. This is one question to ask of the current owner. Do they do a lot of short distance driving (less than 15 to 20 minutes) where the engine does not get fully warmed up? That is tough on oil as well.

Before you spend the money for a 40K mile car you may want to get it checked out professionally.

Good Luck

 

I agree with the condensation, especially if the temp in your area is getting cold. If the motor isn't fully heated up, some will do that. I'll assume the car isn't being driven at the moment and is just started up for potential buyers to hear it run? If you pull the dipstick and theres little water droplets on it, I would drive the car for about a 20-30 minutes and recheck it. If it's a milkshake or the cap still has the crap under it, be prepared for the worst.

 

If the rest of the oil in the engine looks fine I wouldn't worry about it, but if all the oil is milky you have a bad headgasket or a crack somewhere that's causing coolant to mix with the oil.

 

That milky residue is probably because the car has been sitting in the lot for a while.

 

thanks for all the replies, anyway i was doing some thinking and a car @ 40 k miles and it's 7 years old the previous driver didn't drive more then 7 k a year, looks car a car that was driven on short trips a lot and the car came from michigan YEA cold WEATHER,

 

Sounds like a blowen head gasket

 

probably just condensation...

 

change the oil and drive the car for about 40 miles after cleaning the oil cap. if problem persists, you got other problems besides condensation

 

I installed an autozone intake and removed the old air cleaner assembly and when i drive in wet weather i see water accumulation around the area where my air intake is. I have been driving this way for some time and when I wanted to change my engine oil I looked underneath the oil cap and there is a milky substance the same as everyone is describing on this forum. Do you all think this is from my intake taking in water or is it something else? Is there anything to worry about>? thanks for the help. The car idles and runs fine