I have oil built up in my intake system and filter. I read where it said it may be the pcv valve but the valve rattles and seems OK. The hose coming from that valve to the top of my intake manifold is bent and seems to be almost pinched shut. Is there a way I can fix this to where it will stay open? Do you have any suggestions or tips I could try? I get poor mpg, sometimes when I start the van it will idle low and sometimes bog up and down and then die. Sometimes it'll bog up and down and then go to just a little under 1000 rpm. I can feel it lose alot of lower going up a hill or when gaining speed.
My car has an automatic transmission.
Hello. The PCV valve regulates the flow of crankcase fumes to the engine to be burned when there is greater pressure in the crankcase than there is in the engine intake - which is most of the time. If the engine has worn piston rings, there is more combustion gases (also known as "blow by") and pressure in the crankcase, so more oil fumes are vented to the engine, gunking up the throttle body, idle air control valve, mass air flow sensor, etc.
This is somewhat normal over the life of the engine, but also indicates an engine wear condition. Perhaps the hose you mention is a generic hose bent from a straight piece, and instead should be a molded hose that is pre-bent to the correct shape, and has good flow? Check that out. I would recommend having a rough idle inspection completed by a mobile, professional mechanic, such as one from YourMechanic. They will be able to come to your location, diagnose this problem, give you an accurate assessment of damage and cost for repairs.
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