Symptoms
- Misfires, rough idling, hard starting, jerking on acceleration, higher fuel consumption.
What's included
- Worn plugs cause misfires, uneven running, difficult starting, jerks during acceleration and higher fuel consumption; unburnt fuel reaches and damages the catalytic converter. During replacement, we inspect the old plugs: deposit colour reveals much about engine operation. Dry black deposits indicate a rich mixture, oily deposits suggest worn rings or stem seals, and white deposits indicate overheating. We fit plugs with the correct gap and tightening torque: overtightening strips cylinder-head threads and requires a more involved repair. Spark-plug replacement in Kyiv includes torque control to protect the head’s threads.
Additional checks
- Spark-plug gap — checked before installation
- Tightening torque — controlled to avoid stripping the head threads
Why it matters
The soot color on old plugs tells more about engine operation than many diagnostics: dry black points to a rich mixture, oily to worn rings, white to overheating.
More details
Spark plugs determine the quality of mixture ignition. Worn plugs cause misfires, a rough idle, hard starting, jerking on acceleration, and increased fuel consumption, and unburned fuel goes into the catalytic converter and damages it. During replacement we don't just fit new plugs — we read the old ones: the color of the deposits tells us more about how the engine has been running than many diagnostic checks — black, dry deposits point to a rich mixture, an oily film to worn rings or valve seals, white to overheating. We install the plugs with the correct gap and tightening torque: overtightening strips the threads in the head, which is a whole different level of repair. We replace spark plugs in Kyiv with the tightening torque checked, so as not to strip the threads in the head.
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