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Q: oil in throttle body on 1992 Chevrolet Lumina

I am getting poor gas mileage and oil in the throttle body. Car is running rich(code 45). It has a rebuilt engine with about 75k miles and is about 5 years old, the engine anyway. I changed the TPS it gave me a code and IAC and no luck. Thx!
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If memory serves part of the crankcase ventilation system plugs in right at the throttle body on this car. Oil in the throttle body mite be signs of a PCV problem and engine is sucking oil up into throttle body.
Well, that's a relief. The PCV plugs in under the intake plenum and to the intake manifold. I'll switch it out and cross fingers. Thanks, the idle is very erratic, so that makes sense. Thx!
Check the pcv hose at the intake manifold, and make sure the manifold is not clogged shut under the hose fitting!
Also check for excessive blowby vapors out of the top of the valve covers, one at a time on both sides of the engine!Engine idleing,and warmed up to normal opperatin temperature. Place in drive a/t,foot on brake, and slightly accelerate to look for puffing of steam like vapors from top of opening on valve covers.Slow steady smokeing may be normal, for that amount of mileage on the motor.However puffing of vapor can mean one cylinder is loosing compression.Can smell gassy or rich from crancase as well.A compression check can be in order as well!
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