Car Gurus: Oil Question

Nov 5, 2001
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My fiancee's car oil light came on, so i was looking at it last night. The oil had a weird appearance....it was not evenly coating the dipstick, but was on it in puddles and streaks. I seem to remember that this was a sign of something....anyone know?
 

deadlyapp

Diamond Member
Apr 25, 2004
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yeah, im gonna say something is getting mixed with the oil, whether it be water just randomly, or coolant. Does it have any different smell? Drain the oil and check it to be sure.
 
Nov 5, 2001
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It's a Hyundai (yeah yeah yeah). The oil is very dark, as she's about 500 miles past due, and had a slightly burnt smell. The dipstick also had some light brown stains on it. There was no milky appearance or rainbow hue to the oil.

She's going to get an oil change tomorrow, but was curious if there was something else wrong....oil lights don't come on just because you need an oil change.
 

AdamSnow

Diamond Member
Nov 21, 2002
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Sounds like coolant in the oil...

Depending on the year/model of the car you could be looking at a head gasket.
 

rhino56

Platinum Member
Oct 6, 2004
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sounds like the oil is just completely broken down. where is your geographical location? been a hot summer?
 

Spineshank

Diamond Member
Jun 8, 2001
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Originally posted by: AdamSnow
Sounds like coolant in the oil...

Depending on the year/model of the car you could be looking at a head gasket.


For a Hyundai it probably is.
 

Slickone

Diamond Member
Dec 31, 1999
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Originally posted by: MikeyIs4Dcats
It's a Hyundai (yeah yeah yeah). The oil is very dark, as she's about 500 miles past due, and had a slightly burnt smell. The dipstick also had some light brown stains on it. There was no milky appearance or rainbow hue to the oil.

She's going to get an oil change tomorrow, but was curious if there was something else wrong....oil lights don't come on just because you need an oil change.
500 past what? If 3000, it might not need to be changed anyway. The 3K oil change interval (myth) is slowly going away.

Dark oil doesn't always mean something bad. Just that it's doing it's job. Some oil is dark out of the container.

Take a pic of the dipstick and post it here.
 
Nov 5, 2001
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we're in Kansas...it was warm, but not unusually hot. Guess she'll find out when she takes it to the shop...
 

Vette73

Lifer
Jul 5, 2000
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If the oil light is still on I would not drive it. Oil light is for oil pressure. If it is on it means you are VERY low on oil or there is oil but no pressure.

Driving with oil light on = bye bye car.

The only other thing it may be is a bad sending unit. i.e. your car is fine but the oil switch is not working correct.
 

DivideBYZero

Lifer
May 18, 2001
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Originally posted by: AdamSnow
Sounds like coolant in the oil...

Depending on the year/model of the car you could be looking at a head gasket.

Agreed. And for the bashers this can and does happen to a vast amount of car makes, not just Hyundai.
 

radioouman

Diamond Member
Nov 4, 2002
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It sounds like coolant in the oil to me. Have you noticed any coolant usage?
The head gasket seperates three areas: oil passages, coolant passages and cylinders. If you have a break in the gasket between the oil and coolant, the car will run ok but you will get oil in the coolant and coolant in the oil. If the head gasket causes a leak between the cylinder and the coolant passages, you will get coolant disappearing but only when the engine is cold. The pressure from the cylinder will force air/gas into the cooling system when hot, and when it cools it will suck coolant back into the cylinder.

When the oil doesn't cover the dipstick evenly, you have water/coolant mixed with the oil.
 

loic2003

Diamond Member
Sep 14, 2003
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Leaky head/busted oil pump/blown piston....


got any blue smoke coming from the exhaust?
 
Nov 5, 2001
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don't recall any smoke, but I'll check tonight. I did notice a small amount of oil around the corner of the cylinder head, so that probably points to a lown gasket too. The light comes on for a second or so, then goes away. The oil level appearred to be fine.
 

Salvador

Diamond Member
May 19, 2001
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If you can't get a proper reading, the car might be really low on oil. If that's the case, the remaining oil could be getting burned up.

If it's got some kind of a rainbow effect, that sounds like contamination of some sort. If it's milky, that could be coolant in your oil. That's usually caused by a cracked block or a blown head gasket.

It could also have gas in it from a faulty fuel system. The fuel overflows and gets past the pistons. That's no good because when the oil is diluted with gasoline, you're not getting any kind of lubrication.

If the oil light is on though, I would not drive the car, especially after what you're describing with the oil. I would have it towed to the shop. It could be the difference between replacing something minor to replacing the entire engine.