You usually hear this noise when accelerating the vehicle. And that’s also why you hear the pinging and rattling noises. Some of the causes of this condition are improper fuel octane, engine overheating, improper ignition timing, the EGR valve not functioning properly and problems with the computer or knock sensor.
Low Oil Pressure Oil pressure components include variable valve timing (VVT) drivers and hydraulic valve lifters. When there is insufficient oil pressure, these parts may not function, causing rattling in the valves or VVT drivers. Check the oil level first and top it off if needed.
Low Engine Oil Level If the oil level gets too low , you can have a situation where the oil pump sucks air into it and the air gets pumped through the engine along with whatever oil is remaining. This can cause a rattling or ticking noise from within the engine.
Here are 8 Warning Signs of an Engine Going Bad: Check Engine Light Illuminates! This light generally illuminates when detecting engine problems. Loss of Power! Decrease in Gas Mileage! Annoying Noises! Engine Stalling! Odd Odors! Engine Continues to Run after Ignition is Turned Off! Rough Running Engine!
Noise in the Engine Rod knock means there is too much clearance due to the bearing wear, causing the rod big-ends to beat against the crankshaft. Therefore, rod knock is a huge symptom of bad engine bearings and means a bad engine bearing sounds like a knocking sound .
Knocking Noises – If your car engine knocks upon starting the car, there is a good chance that your engine bearings are worn and need to be replaced. In many cases, a bad rod bearing will lead to a ” check engine oil” light being displayed on the dash.
One common problem that will cause a rattle at idle is a failing hydraulic valve lifter. The lifters are small parts that open and close the engine valves, activated by oil (hydraulic) pressure. If you hear a “clack-clack” kind of rattle when you start your car’s engine , it could be a sign of piston slap.
This may happen because of a clogged exhaust pipe, catalytic converter , or muffler. A clogged converter is the most common cause of exhaust back pressure buildup. It will restrict engine airflow, causing the engine to run hotter and lose power, leading to pinging or knocking .
A “ rattle “ sound on light bumps (cracks in road): This is consistent with anti roll bar drop links that are worn out or that have snapped. Notably, this sound often goes away when a vehicle reaches higher speeds.
Valve and tappet noise usually begins as a clicking sound , or chatter, at half engine speed and may then disappear at high speeds. If it does not reduce the noise, the sound may be caused by worn lifter faces or rough cams.
Below are the top oil additives to stop car engine knocking , especially for older engines . 1) Sea Foam SF16. 2) Archoil AR9100. 3) Liqui Moly Cera Tec Friction Modifier. 4) Lucas Heavy Duty Oil Stabilizer. 5) Red Line Break-In Oil. 6) BG MOA Oil Supplement. 7) Rev X Fix Oil Treatment. 8) Lucas Engine Oil Stop Leak.
Listen for a metallic sound that resembles a rattling or scrapping noise . The sound can be intermittent or constant, but it will be a metal to metal contact. Such a noise will reveal a loose timing chain hitting the inside of the timing chain cover every time it rotates. You might also hear a metallic slapping noise .