Bathroom vanity and kitchen sink faucets become loose over time and with much use. Pushing the spout from side to side on kitchen sink faucets results in the faucet body loosening on the sink top. Sink tops that flex such as stainless steel are more susceptible to faucets that loosen. Turning the faucet handles on and off with hard force results in slightly moving the faucet, which over time can cause a wobbly faucet. Homeowners may choose to repair a wobbly faucet themselves to save on costly plumbing contractor repair bills.
Clear away any items being stored under the sink. This allows access to the faucet and provides room for work and tools.
Align the faucet on the sink or vanity top to ensure that the faucet is straight on the sink top. Have another person hold the faucet if the faucet is too wobbly to set firmly on the sink or vanity top.
Lie on your back under the sink to gain access to the faucet and gain a better view of the faucet condition. Faucets generally have plastic retaining nuts on threaded valve body inlets or threaded studs with washers and nuts protruding from the bottom of the faucet through the sink top.
Tighten the plastic faucet nuts; turn the nuts clockwise with a basin wrench to firmly tighten the faucet to the vanity or the sink top.
Tighten models equipped with faucet mounted studs, washers and retaining nuts with an adjustable wrench.
Tighten the retaining nut on single-valve faucet retaining nuts with an adjustable wrench or a socket wrench. The retaining nut on a single-valve faucet is generally located on the underside center of the faucet valve.
Move the faucet spout from side to side, and gently shake the spout up and down to check the faucet for movement. If the faucet base is still wobbly, it's probably because the retaining nuts weren't fully tightened, so go back under the sink to continue tightening the nuts.