I'm a new Volvo owner and I have a puzzling problem. When I try to start my car I have to pump the gas alot AND it won't start unless I loosen the overflow cap on my sealed coolant system. It's a 2000 S40 1.9T . As far as the pumping of the gas pedal, I'm assuming it could be the fuel filter. I know this sounds goofy, but if the engine is cold and I try to start it, there is a lot of pressure build up in the reservoir. I told my son that it was a new type of security system because nobody could dream this up.

 

First thing comes to mind is a head gasket.

 

I sealed the head gasket with a product that I have been successful with before. It no longer spews steam from the tail pipe or the engine. Once started, it runs fine and has never run hotter than medium. I've pulled the spark plugs and there is no water in the cylinders. ( there was water in one of the cylinders before I sealed ). I changed the old oil and filter and it is clean now with no water or coolant. Maybe it just needs more time to seal? Thank you for you response.