2004 1.8 Passat.

Recently, I got the "STOP" message, followed by the "check coolant message". I checked the coolant, and it was a thick baby poop brown sludge. Got the system flushed and a few days later, it happened again. I took it to my mechanic, the water pump, being made out of plastic, was broken. So I had the timing belt, water pump and serpentine belts all replaced. The system was flushed again. 3 days later, the coolant is back to the sludge and got the "STOP" message again. Is there any other explanations for this? Thanks for the help.

 

oil cooler is bad letting oil in the coolant oil cooler above filter
the pump would not have let oil in
replace cooler and you will need to flush it many times

 

Is this an expensive part? I am not familiar with oil coolers. Thanks for the info Jrailer. I will take this to my mechanic and hopefully all will be good after this. What is your opinion onthis VW model with 100k miles with regular maintenance and new timing belts, serpentine belts and new water pump. The car physically is in super shape and this is the only major problem I have had with it. Do these cars hold up fairly well compared to mostafter 100,000 plus miles. Thanks again.

 

oil cooler is very cheap
oil pumps can be a big problem on the 1.8
are you runing synthdic oil ?

 

Should I be running a synthetic oil? I will have to check that out.

 

yes