Oil in IAC

[Chase]

Hello, I have a 1997 Honda Prelude with 175k miles. Standard transmision, upgrades: Aem Short ram intake, Full Greddy exhaust, Tein Coilovers, and a fresh VC gasket. I normally gave burning oil smoke coming out the exhause which i figured was valve seals. I started having an idle problem this morning and went to check the iacv, and i saw oil in it. I’m not sure what would cause this, and what to do. I replaced the pcv valve a few months ago btw.

Topic

[Ingvar]

Any oil in coolant? IACV is coolant operated.

[Chase]

No oil in coolant, or coolant in oil.

[Ingvar]

I am not aware of any oil connections to IACV. I’d say, it leaked from the VC gasket via IACV gasket. Isn’t it right next to it?

[Chase]

I’m getting oil into the intake manifold. I’m thinking due to blow-by

[Lorrin Barth]

All blowby contains some oil. Even engines with good baffling will pass oil as vapor and then the oil vapor can recondense elsewhere. Engines with a PCV valve connected to the intake manifold will have some oil reaching the manifold. As the engine wears and blowby increases, more oil will move to the manifold.

[Gary]

[quote=”barneyb” post=120057]All blowby contains some oil. Even engines with good baffling will pass oil as vapor and then the oil vapor can recondense elsewhere. Engines with a PCV valve connected to the intake manifold will have some oil reaching the manifold. As the engine wears and blowby increases, more oil will move to the manifold.[/quote] Couldn’t say it any better!

[Author]

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