Hi everyone,
I need some advice on the PCV / flame trap routing for my naturally aspirated Volvo 850 with the 10-valve 2.5L engine (B5252FS).
The previous owner did some sketchy "fixes". Currently, the hose coming out of the intake manifold is just hanging down open to the ground. The hose from the oil trap is going into the intake accordion hose, but the manifold side is completely disconnected.
The car is stumbling and bucking heavily under heavy acceleration / wide-open throttle (WOT). I assume this massive vacuum leak from the open manifold hose is causing it to run dangerously lean under load, or the crankcase pressure is blowing spark out.
I know the 10V layout is different from the 20V/Turbo models. I am trying to fix this using a universal Y-piece / T-piece connector since I don't have a new OEM flame trap housing with the vacuum nipple right now.
My questions are:
Should I route a short hose from the top of the oil trap into a Y-splitter, and then run one thicker hose to the accordion pipe and one smaller (restricted) vacuum hose to the intake manifold? Will this layout work safely without sucking raw oil?
Could this unmetered air and messed up PCV setup be the direct cause for the heavy stumbling at wide-open throttle, or should I also look into the distributor cap, rotor, and plugs?
Does anyone have a clear diagram or a real-life photo of how the OEM hoses look around the throttle body on a 10V non-turbo model?