oil in my intake
james moe
12-31-2004, 08:18 PM
i've got oil in my intake and in my air filter box ,does any one knows what could be causing thIS? i'v got a 2001 ford lightning
mjgjr72
12-31-2004, 08:28 PM
bad pcv valve, or the rings are worn and you are getting alot of blowby and and the pressure is pushing oil through pvc system into intake, i would start by replacing pvc valve and air filter
ModMech
01-01-2005, 06:48 PM
The air filter has nothing do do with it, byt the PCV valve might very well play a part.
The PCV system does not connect to the airbox at all on the '97 up Modular engines like you have, the PCV inlet is after the airbox, and the suction is on the engine side of the throttle plate.
On pre-'97 trucks, the PCV takes air directly from the airbox, so oil in the airbox means a broken or worn piston/cylinder/rings.
Given the you are supercharged, it is possible that you have a broken ringland on one piston, but it is not where I would look first, that is the PCV valve.
The PCV system does not connect to the airbox at all on the '97 up Modular engines like you have, the PCV inlet is after the airbox, and the suction is on the engine side of the throttle plate.
On pre-'97 trucks, the PCV takes air directly from the airbox, so oil in the airbox means a broken or worn piston/cylinder/rings.
Given the you are supercharged, it is possible that you have a broken ringland on one piston, but it is not where I would look first, that is the PCV valve.
james moe
01-01-2005, 08:27 PM
The air filter has nothing do do with it, byt the PCV valve might very well play a part.
The PCV system does not connect to the airbox at all on the '97 up Modular engines like you have, the PCV inlet is after the airbox, and the suction is on the engine side of the throttle plate.
On pre-'97 trucks, the PCV takes air directly from the airbox, so oil in the airbox means a broken or worn piston/cylinder/rings.
Given the you are supercharged, it is possible that you have a broken ringland on one piston, but it is not where I would look first, that is the PCV valve.
will it run any different if you had a ringland on a piston is broken?
The PCV system does not connect to the airbox at all on the '97 up Modular engines like you have, the PCV inlet is after the airbox, and the suction is on the engine side of the throttle plate.
On pre-'97 trucks, the PCV takes air directly from the airbox, so oil in the airbox means a broken or worn piston/cylinder/rings.
Given the you are supercharged, it is possible that you have a broken ringland on one piston, but it is not where I would look first, that is the PCV valve.
will it run any different if you had a ringland on a piston is broken?
97chevyman
01-02-2005, 09:38 AM
yeah, you would have lower compression, i bet you just have a bad pcv valve.
ModMech
01-02-2005, 01:33 PM
Nope, a broken ring land will very often not be detectable by how the engine runs. Sometimes, it does not show in a compresion/leak-down test either, they just toss oil.
Most often, a leak-down test will tell you if you have any pistong/ring troubles, even if a ring land is broken. Broken ring lands are VERY common on any supercharged engine that uses Hypereutectic pistons, like this one does (and the Dodge and chevy engines too).
Most often, a leak-down test will tell you if you have any pistong/ring troubles, even if a ring land is broken. Broken ring lands are VERY common on any supercharged engine that uses Hypereutectic pistons, like this one does (and the Dodge and chevy engines too).
Automotive Network, Inc., Copyright ©2026