Ever heard a knocking sound from your car engine when you step on the gas? In technical terms, this sound is known as engine knocking or detonation. The symptoms are usually quite clear: a repeated knocking sound followed by engine vibrations with the same rhythm.

This problem often occurs when the driver needs rapid acceleration or when the car is forced to climb a hill. Although it may sound trivial, knocking is a sign that the combustion process in the combustion chamber is not occurring perfectly. There are various factors that cause this.

1. Poor Quality Fuel

Low-octane fuel can cause the temperature and pressure in the combustion chamber to increase. As a result, the gasoline does not burn completely and leaves residue that eventually sticks to the cylinder walls. Over time, this buildup can trigger knocking.

2. Deposits in the Cylinder

Carbon deposits that accumulate will reduce the combustion space and increase compression. If compression rises beyond the manufacturer's design limits, the engine can trigger knocking every time it works hard.

3. Inappropriate Spark Plugs

Spark plugs play an important role in creating ideal conditions for combustion. If the type is not right, combustion becomes imprecise and knocking symptoms appear. In addition, dirty injectors, damaged knock sensors, problematic piston rings, and engine overheating can also trigger this problem.

Each cause requires different treatment. Many are actually easy to fix, but misdiagnosis can cause the knocking sound to persist. If the symptoms continue, the best step is to take the car to a trusted repair shop for a thorough inspection.

First Steps If You Hear Knocking Sounds for the First Time

If this sound has just appeared and you suspect a problem, try the following:

1. Use Higher Octane Fuel

Make sure it meets the manufacturer's recommendations, which are usually listed in the manual or on a sticker near the fuel cap. On average, cars in Indonesia are recommended to use 90 octane or higher.

2. Check the Condition of the Spark Plugs

Checking the spark plugs is actually simple, but if you are unsure, it is better to take it to a repair shop. After removing them, compare the spark plug model number with the manufacturer's recommendations. If they match and are in good condition, then there are other factors causing the knocking.

Ultimately, knocking sounds should not be taken lightly. The sooner they are detected, the less likely there will be further damage that could be costly to repair.

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Mesin Mobil Ngelitik? Ini Penyebab Umum dan Cara Ceknya

Pernah mendengar suara “ngelitik” dari mesin mobil saat digas? Dalam dunia teknis, bunyi itu dikenal sebagai engine knocking atau detonasi. Gejalanya biasanya cukup jelas: muncul suara ketukan berulang yang diikuti getaran mesin dengan ritme yang sama.

Masalah ini sering muncul saat pengemudi butuh akselerasi cepat atau ketika mobil dipaksa menanjak. Meski terdengar sepele, knocking adalah tanda bahwa proses pembakaran di ruang bakar tidak berlangsung sempurna. Faktor penyebabnya pun beragam.

1. Bahan Bakar Kurang Berkualitas

BBM beroktan rendah bisa membuat temperatur dan tekanan di ruang bakar meningkat. Akibatnya, bensin tidak terbakar sempurna dan menyisakan residu yang akhirnya menempel pada dinding silinder. Lama-lama, penumpukan ini bisa memicu knocking.

2. Ada Deposit di Dalam Silinder

Deposit karbon yang menumpuk akan mengurangi ruang pembakaran dan meningkatkan kompresi. Kalau kompresi naik di luar batas yang dirancang pabrik, mesin bisa memantik knocking setiap kali bekerja keras.

3. Busi Tidak Sesuai

Busi memegang peran penting dalam menciptakan kondisi ideal untuk pembakaran. Kalau jenisnya tidak tepat, pembakaran jadi tidak presisi dan muncul gejala knocking. Selain itu, injektor kotor, knock sensor rusak, piston ring bermasalah, hingga mesin overheat juga bisa memicu masalah ini.

Setiap penyebab butuh penanganan berbeda. Banyak yang sebenarnya mudah diperbaiki, tapi salah diagnosis bisa membuat bunyi knocking tetap muncul. Kalau gejalanya terus berlanjut, langkah terbaik adalah membawa mobil ke bengkel terpercaya untuk pemeriksaan menyeluruh.

Langkah Awal Jika Baru Mendengar Bunyi Knocking

Kalau suara ini baru muncul dan Kamu curiga ada masalah, coba lakukan hal berikut:

1. Gunakan Bahan Bakar Beroktan Lebih Tinggi

Pastikan sesuai rekomendasi pabrikan yang biasanya tercantum di buku manual atau stiker dekat tutup tangki. Rata-rata mobil di Indonesia dianjurkan memakai oktan 90 ke atas.

2. Periksa Kondisi Busi

Pengecekan busi sebenarnya sederhana, tetapi kalau Kamu ragu, lebih baik serahkan ke bengkel. Setelah dilepas, bandingkan nomor model busi dengan rekomendasi pabrikan. Jika sudah cocok dan kondisinya baik, berarti ada faktor lain yang memicu knocking.

Pada akhirnya, bunyi ngelitik tidak boleh dianggap remeh. Semakin cepat dideteksi, semakin kecil potensi kerusakan lanjutan yang berbiaya besar.