Quick Answer:
If you hear loud rattling or grinding in the pipes after using an auger, first stop running fixtures and narrow which fixture causes the sound. Inspect visible drain runs and hangers for loose straps or cracked supports, and listen at a nearby cleanout and joints for grinding that could mean metal-on-metal contact or a remaining auger tip. If the noise lines up with pressure surges, have a plumber pressure-test the system and perform a camera inspection of the joints.
Why This Happens
Using a mechanical auger moves a long flexible cable and head through the drain system. That vibration can loosen straps, crack hangers, or dislodge fittings. Loose pipes can rattle against joists or straps, producing a grinding or clanging noise. In rare cases an auger tip can break off and remain in the pipe, which creates a persistent grinding sound when water or solids pass over it. If the pipe alignment has shifted during snaking, it can also rub at a joint or support — see Drain alignment problems after snaking for more about shifts that follow snaking work.
Step-by-Step What to Do
1. Confirm which fixtures trigger the noise
- Run one fixture at a time: turn on a sink, then the tub, then the toilet, and listen for the moment the noise starts.
- Note whether it happens only with upstairs fixtures, only with outside spigots, or with everything at once. This narrows the location to a branch, stack, or the main line.
2. Inspect visible drain lines and supports
- Look under sinks, in basements, and in crawlspaces for visible drain runs and hanger straps.
- Check for loose or missing straps, cracked or split plastic hangers, and any fresh movement marks on wood or metal where pipes contact framing.
- Lightly tap nearby hangers while someone runs the problem fixture to see if the noise changes — that helps confirm a loose support.
3. Listen at cleanouts and joints
- Open an accessible cleanout (if you can do so safely) and have someone run the problem fixture while you listen close to the joint and the opening.
- Grinding or metallic scraping near a cleanout, trap, or joint may indicate metal-on-metal contact or that a broken auger tip is still in the line.
- If you smell sewage, don’t force the cleanout open further; stop and call a plumber.
4. Check for pressure-related causes and get professional testing when needed
- If the noise happens during rapid valve changes (toilet fill, well pump cycling, or sudden high flow), it may correlate with pressure surges rather than a loose hanger.
- In that case, have a pro perform a pressure test and a camera inspection of suspected joints. A camera will reveal a broken fragment, collapsed pipe, or a joint that has opened and may be rubbing under load.
What Not to Do
- Avoid continuing to run fixtures to “break in” noisy pipes — that can worsen loose joints or allow a broken auger fragment to shift.
- Do not poke into a drain with metal tools trying to find a fragment; you can push the piece deeper or damage the pipe.
- Don’t ignore persistent noises or visible pipe movement. Call a pro when noises persist, you suspect a broken auger tip, or pipes appear to move — these signs can point to damaged fittings or collapsed sections.
When to Call a Professional
- The noise continues after you check visible supports and cleanouts.
- You hear grinding that suggests a metal fragment or rubbing at a joint.
- Pipes visibly move when water runs, or you find cracked hangers that you’re not comfortable replacing yourself.
- There’s a pressure-related noise; request pressure testing and a camera inspection to rule out internal damage.
Safety Notes
- Turn off water to a fixture before working under sinks or opening traps. If you’re unsure which valve controls a fixture, shut off the main water until you’re certain.
- Wear gloves and eye protection when opening cleanouts or inspecting drains — sewer contents can be hazardous.
- Do not insert your hands into a drain or try to fish out objects without proper tools. If you smell strong sewer gas or encounter escaping sewage, stop and call a professional.
Common Homeowner Questions
- Could the auger have left a piece inside?
Yes — a broken tip or cable fragment can remain and cause grinding; a camera inspection will confirm it. - Can I fix loose straps myself?
Often yes: tighten existing straps or add new hangers if you can access the run safely and the pipe material is standard. - Is water-pressure testing really necessary?
When noise lines up with pressure changes, testing helps separate pressure issues from mechanical rubbing and guides the right repair.
More in this topic
For more related fixes and similar symptoms, see Post-Snaking Main Line Problems.