Oil in coolant reservoir?

[Ethan]

I have a 2003 Chevy Malibu that has 115K miles on it. I went to check the oil this morning which was low, so I topped it off. I then decided to check the coolant. When I took the cap off the reservoir I noticed some sticky brown gunk on the cap, and looks like their’s brownish stuff in the reservoir as well.

I have not noticed any leaks under the car. The oil on the dipstick isn’t creamy either.

What could this mean? Thank you!

Topic

[EricTheCarGuy]

It may not be oil. If the coolant hasn’t been changed then it’s likely an issue with the coolant. Dexcool starts out orange but it may end up looking like that over time. Dexcool isn’t the greatest and can do what you describe from time to time when it gets old. You might consider draining out the coolant and putting new in.

Good luck and keep us posted.

[Ethan]

I don’t have any experience doing a coolant flush, but would like to try. Could I get step by step instructions on how to perform a coolant flush on the 03 Chevy Malibu?

Do I do the following?
1. Drain the coolant from the radiator.
2. Refill with water? Do I refill via the reservoir?
3. Let car run til hot
4. Drain
5. Refill with coolant? What type should I use?

[John Hugon]

Do I do the following?
1. Drain the coolant from the radiator.
2. Refill with water? Do I refill via the reservoir?
3. Let car run til hot
4. Drain
5. Refill with coolant? What type should I use?

I would refill with distilled water…. let car run until hot, drain, when flush is done, use antifreeze that is recommended for your car, which is a Dexcool type antifreeze. If the first flush still shows residue in the coolant system you may have to repeat.

I thought Eric had a video on coolant flush….I couldn’t find anything. This is what I came up with.
http://www.carcarekiosk.com/video/2000_Chevrolet_Malibu_3.1L_V6/coolant_antifreeze/flush_coolant

What engine do you have…2.2 or 3.1 L?

[Mike]

Eric is right about how that just kind of happens over time. However, those engines are notorious for lower intake gasket leakage that allows intermixing of coolant and oil, so stay vigilant.

[Glenn]

Blobula, pop out the pcv valve and see if there is any milky brownish sludge on the bottom. Fopeano is correct, often you can catch an early intake manifold gasket leak by examining the pcv valve. It should be located at the right front valve cover.

[Dylan]

I owned your car as my first car and had this issue, NOT TO SAY we have the exact same issue, but I had a chevy tech look around, he said the water pump was bad. I replaced the pump, and there was brown crap all over the blades of the pump, I replaced the coolant, and the issue was gone. Check the weep hole for fluid leakage on the water pump.. also, do you have good heat? And does your car keep temperature good?

[Dylan]

personally… these other gentleman-woman probably have abit more experience with the cooling system than I do. I would recommend their methonds before considering mine, my issue could have been due to the fact my car had 490000 miles when I did this. My car was a escort its whole life until I got a hold of it. I got it around 484K… so it may have been the age and mileage of my car.

[Author]

Replies