I have some smoke coming from the tube that did connect to my intake. I have just noticed this after I deleted all the hoses that connect to the intake. They all broke so I said to hell with them because my enterprise intake is almost complete. Is this because I don't have a pcv system or is it just normal? i have heard that pressure can build up under the valvecovers but how is that possible if it isn't air tight? I have a nipple on my crx intake but that is being used for my fuel vapor line, the one that did go where my canister was.

The PCV system is quite an important part to the oiling system of your motor. As you see in many preformance builds of motors people put on the crank case breathers on the valve covers with the filters on them. The idea behind this is that blowby happens in limited amounts in all motors, so eventually there will be positive pressure in the crank case. When the crankcase is charged with pressure, oil stops flowing in behind your pistons. The pistons suck the oil up behind them to coat the cylinder walls and lubricate, if your PCV system isnt working right positive pressure builds, and it creates air bubbles in the crankcase that prevents oil from circulating behind the pistons. GM found there was gas fumes inside this blowby air, so they put a little check valve on it and recirculated it to the intake for a bit of extra gas mileage.

Anyway, now that I have the whole PCV speach out of the way, any activity through the PCV spot on your valve cover indicates what is actually going on inside the crankcase of the motor. Common with old motors is extensive amounts of blowby and huge amounts of pressure being built up. Usually a massive amount of air coming out of this port indicates a blown piston ring. Smoke is in ways a more common and a more rare thing to find from a PCV hole, as there is no one reason there should or should not be smoke coming from there. In most cases it is caused by blowby igniting small amounts of oil, but it could be caused by failed or close to failed bearings creating exessive heat and burning oil. In either case I suppose it involves burning some sort of oil and nothing else, neither are good or normal in most cases, unless it is in very small amounts.

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Time to iron out the kinks.....

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Dark pretty well has this covered, however,I would like to add to this thread. The pcv system is just a modern version of the old down-tubes found on pre-1960s flat heads and proabably earlier engines. Yes, the system relieves back pressure in the crank-case, but it also deleted the oily fumes that used to eminate from the bottom of the old down-tubes that undoubtedly often made their way into the passenger compartments of older cars. The system also allows a "reburning" of these gasses and moves their exit point to the back of the vehicle. Besides, under the old system, the tube was often shaped so that a suction was created at the end of the tube when the car was moving. However, when the car was still, the gasses were left to vent under positive exhaust pressure, hence contributing to the pollution of the motor oil(1,000 mile oil change intervals were common). So, I'd buy the parts to reassemble the system if it was me.

My old Duke would blow some smokey-looking gas out the oil fill hole if I removed the cap. But the engine had almost 200K miles on it, and the piston rings were trashed. My freshly-rebuilt V6 doesn't do that.

Some sort of PCV system is better than none. Not only does it reduce contamination (of both the engine oil and the air), but it's a safety issue. Those noxious gasses are flammable. In a Fiero, that's asking -- actually begging -- for trouble.

My solution for the PCV system involved a K&N breather filter, and a short piece of pipe running from the PCV valve to the intake manifold. Hey, it works. And it's alot cleaner looking than the stock setup.

Older engines also had big tubes coming up from the oil pan with breathers on them and also breathers on the valve covers. While they worked good and looked nice (the chrome breather caps) they tended get staurated with oil and also get oil all over the covers etc. Keep your PCV, it dont hurt proformance none anyway.