Fuel smell in oil, and also burns aprox. 1 qt. of oil in 300 miles of use. Just had the engine rebuilt due to valve clatter,smoking on acceleration and start-up

1 a simple compression test will tell you if the rings and valves are bad. thats where you start.. 2 it could be an oil leak under the vehicle , you will see a black spot. do this first it only takes a look whee you park it on dry clean pavement or place a clean piece of cardboard under it.

More than likely u have a leaking valve cover gasket unless your seeing smoke than it might have a burnt valve guide or guides if its smoking real bad than it could have bad rings and you don't want that cause then u half to tear the motor down basically rebuilding the motor

Blue smoke (how many miles on engine, 50k or 500K???????
to some this means, burning oil, others steam
it that blue smoke lingers a long time that is oil burning
and smells just like oil burning.
and means 2 things,
1: engine burns oil.
2: if car had autotmatic trans the vacuum modulator love fail
and suck ATF fluid to the intake plenum and burn it, and bingo burning oil like mad.
3: PCV valve packed solid,and forces engine to leak oil or burn oil. or both. this is a 50k miles service point, skipping this?
4: gas in the oil making it thin and not sneaks past valve stems.
does oil change cure this.>?

now engines.
worn out engines smoke. (burn oil)
as do bad valve guides and seals.
and bad piston rings.
100 years same story, and miles matter. History on engine too.
matters.

White smoke is usually an indication of burning antifreeze and burning oil would have a more bluish tint to it and smell like burning oil. If it's a 2012, isn't it still covered by the KIA warranty though??

Valve seal leaks will cause an engine to smoke on start until the oil burns off. If a head gasket were leaking it would be smoking constantly.

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is the car smoking blue or is the oil leeking out ?

if the is consuming oil by buring it while driving the faults are either :

Valve seats / Burnt valves
Piston Rings
or sump compression which can force oil into the combustion chamber causing it to burn it and expel the burnt oil via the exhaust system.

Either way, its going to pretty expensive on a 2002 5 series.

If you have no visible signs of oil leaking out of the engine then the oil is being burnt. By visible leaking I mean a small puddle of oil under the car after having been left overnight. This can be cured by replacing shaft seals and gaskets. Burning oil is visible as smoke under deceleration (no throttle) and under full power(flooring it). This is due to worn/old valve stem seals(smoke under deceleration) and worn oil rings(smoke under acceleration) This can only be cured by a major engine overhaul or engine replacement. Bear in mind that losing a pint of oil in 1000 miles is acceptable.

I think, the bearing of the A/C unit jam and putting extra load on the engine or the belt that connects to the engine has dried out. Logically, A/C has no direct connection with the engine exhaust.

the dealer is right its a valve stem seal, when it sets valve not moving oil when hot will seap down thru valve seal into combustion chamber hense oil smoke when you start it up. its burning oil when your going down the road you just cannot see it because its such a mynute amount, because oil is moving and dosent get a chance to run into cyl. like it does when its setting, but its burning it. if its fouling a plug its bad and may be more than just a valve like maybe oil ring on piston. i got 40+ years of experance working on autos and trucks and if its using that much oil in just 100 mi. you got to be seeing something.

cylinder head gasket???