Can a vacuum leak cause a single cylinder misfire?

If the leak is near one intake runner, yes. But usually vacuum leaks cause P0300 (random/multiple).

What if new plugs and coils do not fix it?

Check fuel injector operation and run a compression test. Low compression means valve or head gasket issue.

High Severity

Ignition System

Cylinder 4 is misfiring.

Common Fix

Replace spark plug or coil

Estimated Cost (DIY)

$5 - $80

Bad spark pluglikely

Faulty coillikely

Bad injectorpossible

Low compressionpossible

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Can a vacuum leak cause a single cylinder misfire?: If the leak is near one intake runner, yes. But usually vacuum leaks cause P0300 (random/multiple).
What if new plugs and coils do not fix it?: Check fuel injector operation and run a compression test. Low compression means valve or head gasket issue.

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