C4 2005 - Oil in the coolant reservoir

[Passanger5555]

Hello all!

I have a problem with my Citroen C4 2005 2.0 petrol (with lpg system).

I have seen that the coolant is dirty with oil probably but the dipstick looks clean. I have had a problem half a year ago with the oil radiator that was leaking oil in the coolant but it was changed with a new one.
Im a bit confused if it can be the head gasket or the oil radiator again. I will be taking it to a mechanic but id like some advice first as i dont wanna go clueless. So far the temps looks kind of normal but i dont want to overlook this problem now. A few images attached for additional info.

Thank you!

[GiveMeABreak]

You need to provide some more details (preferably the VIN) so we can see exactly what vehicle options you have.

[Passanger5555]

Sure, this is the VIN number : VF7**************[VIN obfuscated, can be read by forum staff]

[ozvtr]

What do you mean by the "oil radiator"? Is your car an automatic? Do you mean the gearbox oil heat exchanger?
You need to determine if the oil in the coolant is engine oil or transmission oil (if it's an auto).

[Passanger5555]

Ah, sorry for any confusion. Yes its an automatic. Its an exclusive model from 2005 with an Ew10A RFJ engine (at least this is what i have found) 103 kw. The part that i thought was the engine oil cooler looks almost exactly like this : https://www.xdalys.lt/en/product/14953082555/ , and is placed directly on top of the oil filter.

This is my first car and i have thought this whole time that it was the engine oil cooler.

Regarding the dirty coolant which looks like oil mixed i cannot tell now if its the transmission oil or engine oil. I know that half a year before i had the exact problem and it was fixed after replacing the oil heat cooler (the part as in the link)

[GiveMeABreak]

So you have the AL4 Automatic transmission. Check the oil radiator as if these fail you'll get oil in the coolant and that 'mayonnaise' (emulsified oil) in the expansion tank. Failing that Head Gasket failure can be another cause.

[Passanger5555]

The moment i change the oil cooler i will also need to clean the water system but do i need to add transmission oil or change it completely? Currently im using the Liqui Molly Top Tec ATF 1200.

[ozvtr]

You need to drain the oil in the transmission and inspect it. You may have coolant in the transmission oil. Water is not a good lubricant.
Oil in the coolant wont cause any damage but water in the transmission oil is no good.

[Passanger5555]

Thanks, i will be talking with the service shop and i will give update

[Passanger5555]

Update on this matter

I spoke with the mechanic and they told me that the oil must be remnant from the time i actually head this problem and even flushing the system a couple of times would not entirely solve the problem.
I have driven quite a lot now and it seems that there is no problem.

The oil was actually on top only and if you can see the first pic half of the stick has oil and the the lower half is clean with the red coolant.

Also this part https://www.xdalys.lt/en/product/14953082555/ seems to be a oil cooler / heat exchanger for the engine oil not the transmission but im still not 100% sure.