In October I started smelling coolant in the van when I was driving. Since then I've had the timing chain gasket, the coolant reservoir tank, the intake manifold gasket and a new radiator cap replaced and I can still smell coolant. It's been pressure tested at two different garages and they both said it's not the head gasket, but today it made an odd noise when I started it and the engine sounds loud (grumbling sort of noise) and it's making a whining noise when I accelerate. Please help!