The bouncing needle of the tachometer

Podczas jazdy i na postoju, przy około 2000 obr./min igła przeskakuje, silnik ma normalną moc, a wszystkie świece zapłonowe są brązowe. Co może być przyczyną?


While driving or idling, at approximately 2000 rpm, the needle skips, the engine has normal power, and all the spark plugs are brown. What could be the cause?

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The tacho pulse comes from a "node" crimped connection in the loom for the ignition system. Over time these connections corrode. You could check that