Knock sensor replacement cost
Knock sensor circuit faults (P0325 and related) can reduce power via timing retard; labor often dominates because sensors are buried under intakes.
Typical U.S. independent-shop price range
$417–$589 national average for knock sensor replacement.
- Labor: $291–$427
- Parts: $126–$161
- Source: RepairPal — price data as of September 3, 2026. Excludes taxes, fees, diagnostic time, and your location. Related repairs may be needed.
What’s usually included
RepairPal’s average covers knock sensor parts and labor. Intake removal, gaskets, and wiring repairs may be a large share of the bill — ask for labor hours and whether gasket sets are included.
Dealer vs independent
Access labor can be similar at dealer and independent shops; parts markup differs. Get a written labor-hour breakdown before authorizing, especially on V6/V8 engines with manifold removal.
Common upsell red flags
- Sensor replacement without circuit resistance/signal testing
- Premium “performance” sensors that don’t address a wiring fault
- Broad engine teardown quoted from a knock code alone
More patterns: spotting upselling.
Questions before you authorize
- How many labor hours are estimated, and what must be removed?
- Did testing point to the sensor vs the harness?
- Are intake gaskets and related seals included?
- Will you verify timing advance / knock feedback after the repair?
Also see before you authorize a repair and how to read a repair estimate.
DIY vs shop
Often not DIY — buried sensors and torque specs matter. Mis-torque or damaged threads create new problems. Prefer a shop for manifold-out jobs.
Confirm the code before you authorize (disclosed)
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For sensor and emissions jobs, a reusable Bluetooth OBD-II scanner helps you capture codes and live data before paying for “mystery” diagnostics. One option: BlueDriver Bluetooth Pro OBD-II scan tool (BlueDriver/Levanta affiliate). Any capable OBD-II reader is fine — this is not required to use Fair Auto Shops.
Optional tools (disclosed)
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- Mechanix Wear Original work gloves (Medium) — Intake-out knock sensor jobs are messy; gloves help. Pick your size on Amazon if Medium isn’t right.
Related codes: P0325
FAQ
How much does knock sensor replacement cost?
According to RepairPal, the U.S. figure is $417–$589 for knock sensor replacement (price data as of September 3, 2026), excluding taxes, fees, and location. Your vehicle and region will differ.
Why is a shop quoting more (or less) than the national average?
Labor rates, OEM vs aftermarket parts, vehicle packaging, diagnostics, and related repairs move the number. National averages on this page exclude taxes, shop fees, diagnostic time, and your location. Ask for a line-item estimate and compare with a second independent shop.
What’s usually included — and what’s excluded?
RepairPal’s average covers knock sensor parts and labor. Intake removal, gaskets, and wiring repairs may be a large share of the bill — ask for labor hours and whether gasket sets are included. Cited ranges exclude sales tax, shop fees, diagnostic time, and regional labor-rate differences unless a source on this page says otherwise.
Can I DIY this, or should I use a shop?
DIY-able rating on this guide: No. Often not DIY — buried sensors and torque specs matter. Mis-torque or damaged threads create new problems. Prefer a shop for manifold-out jobs.
Does this page tell me if it’s safe to keep driving?
No. Cost ranges are not a drivability diagnosis. Confirm symptoms with a shop; use the questions on this page before you authorize related work.
What upsell red flags should I watch for on this job?
This guide flags: Sensor replacement without circuit resistance/signal testing; Premium “performance” sensors that don’t address a wiring fault; Broad engine teardown quoted from a knock code alone. More patterns: /upselling.
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