2001 saturn sc2 rocker arm suspected

could possibly be a lifter tapping (Ticking) ,depending on how many miles the vehicle has on it might be time for lifters to be adjusted,most foreign overhead cam engines must have lifters adjuster periodically ,if you turn on the air its puts more of a load on the engine causing a louder sound (also check oil level an engine low on oil will start to tick too.. the more wear the engine gets the looser the lifters can get over time ,look in your service manual if you have one and see what the intervals are on lifter adjustment this can give you an idea.
possible only if
the ticking sound is coming from the top of the engine usually comes from under the vavle covers where the lifters are located,

If there was a problem that caused the rocked to become dislodged I would have checked the rocker bushes and shaft and replace both. The rocker where it works on the end of the valve wears a recess that will move and then click back into place. I would use a 20w-50 grade oil and additives work at reducing friction . IF you need it to thicken the oil then there is something worn out.

Your hearing lifter noise common in most cars in cold weather I have a 2001 sc1 same engine as yours here's how to get rid of that ticking sound go buy a quart of Lucas synthetic motor treatment change your oil and leave it 1 quart low add the Lucas synthetic oil stabilizer within 1 week you will not hear the noise agian reason your hearing the noise is there's no oil at the top of the engine on a cold start oil when cold is thicker hints why your noise in your engine what Lucas does is eliminate the dry start by the way my engine has 288,000 and does not use a drop of oil after you use this product you should use it every oil change you will see your car will thank you regards Chris

Hi there:
First I suggest check this information about "engine noses"...
ENGINE CLICKING NOISES
A clicking or tapping noise that gets louder when you rev the engine is probably "tappet" or upper valvetrain noise caused by one of several things: low oil pressure, excessive valve lash, or worn or damaged parts.

First, check the engine dipstick to see if the oil level is low. If low, add oil to bring it back up to the full mark. Is the engine still noisy? Check your oil pressure. A low gauge reading (or oil warning light) would indicate a serious internal engine problem that is preventing normal oil pressure from reaching the upper valvetrain components. The cause might be a worn or damaged oil pump, a clogged oil pump pickup screen or a plugged up oil filter. Using too thick a viscosity of motor oil during cold weather can also slow down the flow of oil to the upper valvetrain, causing noise and wear.

COLLAPSED LIFTER NOISE
Worn, leaky or dirty lifters can also cause valvetrain noise. If oil delivery is restricted to the lifters (plugged oil galley or low oil pressure), the lifters won't "pump up" to take up the normal slack in the valvetrain. A "collapsed" lifter will then allow excessive valve lash and noise.

VALVE LASH NOISE
If you can rule out lubrication-related problems as a cause, the next step would be to remove the valve cover(s) and check valve lash. On older import engines, mechanical lifters require periodic valve lash adjustments (typically every 30,000 miles). Too much space between the tips of the rocker arms and valve stems can make the valvetrain noisy -- and possibly cause accelerated wear of both parts.

To measure (and adjust) valve lash, you need a feeler gauge. The gauge is slid between the tip of the valve stem and rocker arm (or the cam follower or the cam itself on overhead cam engines) when the piston is at top dead center (valve fully closed). Refer to a manual for the specified lash and adjustment procedure. Also, note whether the lash spec is for a hot or cold engine (this makes a big difference!).

On engines with hydraulic lifters, oil pressure pumps up the lifters when the engine is running to maintain zero lash in the valvetrain. This results in quiet operation. So if the rocker arms are clattering, it tells you something is amiss (bad lifter or worn or damaged parts) or the rocker arms need adjusting.

DAMAGED ENGINE PARTS NOISE
Inspect the valvetrain components. Excessive wear on the ends of the rocker arms, cam followers (overhead cam engines) and/or valve stems can open up the valve lash and cause noise. So too can a bent pushrod or a broken valve spring.

RAPPING OR DEEP KNOCKING ENGINE SOUND
Usually bad news. A deep rapping noise from the engine is usually "rod knock," a condition brought on by extreme bearing wear or damage. If the rod bearings are worn or loose enough to make a dull, hammering noise, you're driving on borrowed time. Sooner or later one of the bearings will fail, and when it does one of two things will happen: the bearing will seize and lock up the engine, or it will attempt to seize and break a rod. Either way your engine will suffer major damage and have to be rebuilt or replaced.

Bearing noise is not unusual in high mileage engines as well as those that have been neglected and have not had the oil and filter changed regularly. It can also be caused by low oil pressure, using too light a viscosity oil, oil breakdown, dirty oil or dirt in the crankcase, excessive blowby from worn rings and/or cylinders (gasoline dilutes and thins the oil), incorrect engine assembly (bearings too loose), loose or broken connecting rod bolts, or abusive driving.

Bearing wear can be checked by dropping the oil pan and inspecting the rod and main bearings. If the bearings are badly worn, damaged or loose, replacing the bearings may buy you some time. But if the bearings are badly worn or damaged, the crankshaft will probably have to be resurfaced - which means a complete engine overhaul or replacing the engine is the vehicle is worth the expense.

ENGINE PINGS OR KNOCKS WHEN ACCELERATING
The cause here may be Spark Knock (Detonation) caused by an inoperative EGR valve, overadvanced ignition timing, engine overheating, carbon buildup in the combustion chambers, or low octane fuel.

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

This sounds like a tappet (cam follower/rocker arm) is at max clearance. This can be the sign of cam lobe wear or follower wear on its internal clearances or valve tip wear.

the ticking , if you hear it on the top of the motor, will be a rocker arm,, it could be plugged and not getting oil, if its coming from lower down in the motor, it is possibly a stuck valve,, or a rod bearing , if its a ticking noise its more than likely the rocker assembly,, if its more of a knocking noise its lower in the motor

What kind of sound? If it's a ticking sound from inside the valve cover it could be a bad rocker arm, worn lifter or lifter & cam lobe or broken valve spring (needs to be looked at). If the noise is deep and best heard at the oil pan. it could be a rod bearing or main beginning to go but generally, that lowers oil pressure. Another item that sounds nearly the same is a cracked flywheel. Careful listening can often unravel this or have a very experienced tech look at it....(still your choice on who does the repair).

I have a 2002 with 130,000 and it ticks,but goes away after 2 min,if yours continues to tick you may have a rocker arm that is getting lose or a lifter that is not pumping up.

probably a rocker arm out of ajustment or a collapsed or failed lifter. would have the valve covers pulled and the rocker arms felt of

if high milage motor seems fine leave it as is-not proper way to fix either have worn cam, rocker, or bad lifter. old chevy motors with car running was zero latch no ticking 3/4 to 1 turn to center lifter plunger