Hyundai Sonata Parts And Hyundai Sonata Accessories
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Hyundai Sonata Excessive Engine Noise: Four Possible Culprits
In a car that\'s as sophisticated, as athletic, and as edgy as the Hyundai Sonata, too much engine noise is a big no. So as soon as you notice strange noise coming from your engine, you\'ve got to give it a thorough check to find out the cause of that bothersome noise. Most of the time, unusual engine behavior means a trip to your trusted mechanic. While that\'s kind of the right thing to do knowing how complex today\'s engines are, it won\'t hurt if you have an idea of what\'s going on under the hood before you let the expert do the checking. This way, you\'ll know what to expect and you can have an idea on how much the repair or replacement will cost you. To help you with that, here are some of the possible causes of the excessive noise under the hood of your Hyundai Sonata:
Faulty or misaligned connecting rod
If your ride\'s connecting rod is misaligned, you\'ll hear light pounding or knocking sound that\'s more noticeable when your engine is at an even rpm, meaning, it\'s not accelerating or decelerating. This kind of noise, however, can also be caused by a worn crankpin or bearing as well as lack of oil. To find out if it is indeed the connecting rod that\'s producing the unusual noise, you can conduct a cylinder-balance test. This is done by shorting out the spark plugs one cylinder at a time while the engine is running. You\'ll easily find out which connecting rod is faulty because the noise will lessen if the rod\'s home cylinder isn\'t delivering power.
Worn-out bearings cause crankshaft knock. This heavy yet monotonous metallic knock is more noticeable when your Sonata is accelerating or is under load. Since there are a number of bearings in the engine, you have to pay close attention to the knocking to find out which bearings are causing it. Worn-out main bearings produce a regular, rumble-like knock while defective rod bearings cause more distinct knocks. If you\'re hearing irregular, sharp knocks, then you\'ve a worn-out thrust bearing in your crankshaft.
Problems with the valvetrain, particularly too much valve clearance and faulty hydraulic valve lifter, can lead to tappet noise which usually starts off as clinking sound when the engine is at half speed and typically disappears as the engine gets to high speeds. Checking the valve clearance can be done by inserting a thickness gauge in the gap between the valve stem and the rocker arm or lifter. If doing so minimizes the noise, then you\'ve got the cause of that clicking sound, and you can remedy that by making the necessary adjustments in the valve clearance. If doing so didn\'t reduce the noise, you have to do more troubleshooting. Other possible culprits are rough cams, worn lifter faces, loose lifters, and weak or damaged valve springs.
Worn piston rings or cylinder walls
These problems produce light knocking or pounding sound that\'s more evident during acceleration. Troubleshooting the cylinders can be done by taking out the spark plugs and adding engine oil into each cylinder before cranking the engine for several revolutions to allow the oil to work down past the piston rings. Put the spark plugs back and turn on the engine. If the noise has been minimized, then the culprits are your piston rings.