jjyerro

Hi, I have Audi a4 b5 1.8. The oil is mixing with my coolant, what do you think is the problem of my car? The coolant on my tank looks like a milkshake, and I am thinking that it's a great idea if i sip a little hahaha.

I check my oil cooler and replace the O ring cause there is a leak on that part.

The other problem is that when I turn off the car, my coolant reservoir is overflowing.

I need help!

Prospeeder

I would start with replacing the oil cooler. Its the thing the oil filter bolts to. Its not too uncommon for them to fail and cause oil into the coolant.

I would suggest replacing the oil cooler, changing the engine oil. Flush the cooling system with a hose best you can, use a degreaser like super clean, purple power, what ever, and fill the system, and then run the car till it gets slightly warm, not hot. Remove the thermostat, radiator hoses, flush flush flush flush. Remove heater core lines, flush out heater core. When you feel like you got as much as possible out. Replace the coolant reservoir and cap. They are super cheap and cleaning the old one is impossible I have found.

Doing this is the best results I have gotten, I have had probably 5-6 cars in with this issue before.