Hi folks,
So My 1.9 gas engine had a concern last year.  It seemed to be getting air in the coolant system and then not bleeding out.  I never identified the problem.  A friend gave me a original VW blue cap and my problem seemed to go away.  I added some coolant to the reserve tank after the new cap and it was sucked in and the level maintained for about a year.

Returning from a three hour pretty hard trip we noticed my van leaking coolant.  It was coming out the top of the overflow tank. I decided to continue the hour trip home as the temp was fine.

No more coolant seemed to leak out.  Now that the van is cooled off the reservoir is full and the over flow tank is empty.

Last year folks gave me some good suggestions as to what might be going on.  As the blue cap seemed to solve my problem I chose to hope all was well.

I think this cap is working correctly so my fear is that this means exhaust gas getting into my coolant. 

Can folks offer me ideas again.  The van is running great otherwise. 

I have a long trip planned in about two weeks and would like to take the van but this is concerning.

I know the engine will need replacing eventually as it has about 140,000 miles on it.  
        I’m good with a future healthy engine but would like to keep this one and keep saving as long as reasonable.

Any new or old thoughts on my situation is greatly appreciated.

Eric Caron 
85 GL Auto Westfalia