How to Deal with Engine Piston Slap in Cars?

3 Answers
OSteven
07/29/25 11:44am
Car engine piston slap can be addressed by: 1. Fixing the engine speed at the position where the knocking is loudest and conducting a cylinder cut-off test; 2. Checking for bending or twisting deformation of the connecting rod; 3. Removing the fuel injector, adding a small amount of engine oil into the cylinder through its installation hole, and cranking the diesel engine several times with the starter to ensure the piston and cylinder wall are fully lubricated before starting the engine. The causes of engine piston slap include: 1. Excessive wear and excessive clearance between the piston and cylinder; 2. Incorrect piston orientation or piston deformation; 3. Poor lubrication of the cylinder wall; 4. Bending or twisting deformation of the connecting rod; 5. Clogged lubrication oil passages; 6. Severe carbon buildup in the combustion chamber.
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DeLeonardo
08/13/25 8:24pm
I've been driving for many years, and engine knocking is quite common. The sound, usually like metal clanging, is often caused by incorrect ignition timing or poor fuel quality. First, try using higher-octane gasoline, such as 95 or above, which can sometimes alleviate the issue. If the knocking persists, check if the spark plugs are worn out or if carbon buildup is clogging the fuel injectors. Remember to address it promptly; otherwise, engine wear will worsen, and repairs could cost thousands. It's best to take your car to a reputable repair shop for a diagnostic check with professional equipment. Also, have them inspect the air filter and engine oil condition to ensure safe driving and prevent similar issues. Don’t cut corners by using cheap fuel—regular maintenance can prevent problems before they arise. Always take it seriously; don’t wait until a major issue occurs to act.
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PaigeAnn
10/08/25 6:14am
Last month, I encountered a similar issue while driving—the engine was making a knocking sound, and my friend said it was engine knocking. I panicked and immediately filled up with higher-octane gasoline, which slightly reduced the noise. Then, I went to a small repair shop to check the spark plugs, and they were indeed dirty, so I replaced them with new ones. My advice is not to push through and keep driving if you notice abnormal sounds after starting the engine. Pull over safely, turn on the hazard lights, and call for a tow truck or a mechanic. Always fuel up at reputable gas stations like PetroChina or Shell to prevent such issues. Don’t ignore small problems—if they lead to engine damage, repair costs could run into tens of thousands. Safety first!
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