P0328 Code: Why GM 5.3L Vortec Owners See This So Often

P0328 Code: Why GM 5.3L Vortec Owners See This So Often

STOP — GM 5.3L Vortec? This Is the Valley-Pan Problem

P0328 Code: Why GM 5.3L Vortec Owners See This So Often

A P0328 code on most engines is a relatively cheap fix — a $50 sensor and a connector clean. On GM 5.3L/6.0L Vortec trucks it's notorious because the sensor lives under the intake manifold, but even then the parts cost stays under $300. This guide shows you exactly how to find the real cause before paying for shop diagnostic time.

Updated May 2026 14 min read DIY Difficulty: Intermediate Fix Cost: $20 – $600
⚡ QUICK ANSWER

P0328 means the Bank 1 knock sensor circuit is reporting voltage above its normal 0.5–4.5V range — the PCM has lost confidence in the sensor and disabled knock-based timing protection. The fixes, in order of probability: (1) rule out real engine knock by listening for pinging and checking coolant temp, (2) inspect the knock sensor connector for corrosion or water intrusion, (3) replace the sensor with an OEM part ($20–$150), (4) replace the wiring sub-harness on GM trucks. Engine internal work is almost never required — but real detonation, if present, must be addressed first to protect the engine.

What Does P0328 Actually Mean?

Your vehicle's knock sensor is a piezoelectric vibration sensor — essentially a microphone listening for the high-frequency rattle of engine detonation. It's threaded into the cylinder block (Bank 1 = the side where cylinder #1 lives) and feeds a voltage between roughly 0.5V and 4.5V back to the PCM. When the sensor "hears" knock, the PCM retards spark timing to protect pistons and rod bearings from damage.

P0328 sets when the PCM detects the knock sensor signal voltage exceeds about 4.5V for more than 5 seconds — well outside the normal operating range. The cause is usually an internally failed sensor (open or short to power), a wiring fault, or — less commonly — a real engine knock condition that's saturating the sensor. With P0328 active, the PCM falls back to a conservative spark timing map, costing you power and fuel economy until the sensor signal is trustworthy again.

Why "high voltage" matters: A piezoelectric sensor outputs a small AC-like voltage proportional to vibration. With no knock the signal should sit near the 0.5–1.0V baseline. "Circuit high" means the wire is floating at the supply voltage — typically because the sensor's internal element is shorted to its case, or the signal wire has shorted to a 12V supply somewhere in the harness.
Critical: P0328 is almost always an electrical/circuit fault, NOT actual engine damage. Don't authorize valve, piston, or rod bearing work as a first step. But before assuming it's "just the sensor," listen for actual pinging under acceleration and verify the cooling system — if real knock is happening, the engine needs that first.

What Are the Symptoms of P0328?

P0328 produces noticeable drivability changes because the PCM defaults to a conservative spark map when it can't trust the sensor. Most owners notice a power drop before they even scan for codes:

Check Engine Light — always present; sometimes paired with P0327/P0332/P0333
Engine knock or pinging under load — especially during hard acceleration or climbing hills
10–20% drop in fuel economy — conservative timing wastes fuel
Reduced power and hesitation — retarded timing softens the throttle response
Engine running slightly hotter — retarded timing pushes more heat into the exhaust
No stalling or starting issues — the engine still runs normally on its safe-mode map
The "flat power band" tell: Many drivers describe a P0328-affected engine as "feeling like the throttle response just disappeared." If your vehicle suddenly feels gutless above 3,000 RPM and you smell a slightly hotter exhaust, scan first — it's often a knock sensor circuit fault, not an internal engine problem.

Is P0328 Code Serious?

It's moderate in severity — drivable but not safe to ignore long-term. The code itself is electrical and won't break anything. The real risk lies in what it disables: the engine's knock protection. Five concrete consequences of ignoring P0328:

Power loss — noticeable under acceleration and on highway grades
10–20% MPG drop — verified through fuel-economy data reported by owners
Failed emissions inspection — P0328 keeps OBD-II readiness monitors incomplete
Detonation damage risk — if real knock is happening, no sensor feedback means no PCM protection
Catalyst damage — chronic misfires/knock dump unburned fuel into the cat

The good news: most P0328 cases are pure circuit issues — failed sensor, corroded connector, or chafed wire. The cheap diagnostic test is to listen for actual pinging under hard acceleration. No audible knock = treat as a circuit code (cheap fix). Audible knock = address the engine cause immediately.

Severity rating: 🟡 Moderate — repair within 2–4 weeks if there's no audible knock; immediately if you hear pinging or rattling. The typical fix is well under $300 in parts; only GM 5.3L/6.0L jobs run higher due to labor.

What Causes a P0328 Code? (Ranked by Frequency)

Check causes in this order. Industry data shows roughly 65% of P0328 cases are the sensor itself — but always rule out real engine knock first, since that's the only cause that can cascade into actual engine damage.

1

Failed Knock Sensor (Internal Element)

The single most common cause (~65% of cases per industry repair data). The piezoelectric element fails internally — either open or shorted to its case — which sends the signal voltage stuck high. Common after long mileage, high heat exposure, or coolant contamination. Always use OEM (e.g., AC Delco, Delphi, Standard Motor Products) — generic aftermarket sensors are notorious for false codes.

Fix: $20–$150 part · 30 min – 3 hr (engine-dependent)
2

Wiring / Connector Corrosion or Short to Power

A textbook "Circuit High" cause is a signal wire shorted to a 12V supply somewhere in the harness. On GM 5.3L/6.0L Vortec trucks the sub-harness is famously vulnerable because it sits in a recess under the intake where water and coolant pool. Inspect the 2-pin connector for green corrosion and chafed insulation.

Fix: $20–$200 harness + labor
3

Real Engine Knock (Detonation)

Less common but the most important to rule out. Low-octane fuel in a high-compression engine, carbon buildup on pistons, excessive engine load, or a lean fuel mixture can produce real detonation that saturates the sensor. If you can hear pinging or rattling under acceleration, fix the underlying cause (octane, carbon, fuel mixture) before chasing electrical faults.

Fix: $10 (fuel) – $300 (carbon cleaning)
4

EGR System Stuck Open

A stuck-open EGR valve introduces too much exhaust into the intake, leaning out the mixture and inducing knock. The sensor reports real knock, the PCM sets P0328. Test EGR operation before replacing the knock sensor — especially if P0401/P0402 EGR codes are also present.

Fix: $80–$300 EGR valve
5

Cooling System Overheating

Chronic overheating causes pre-ignition and detonation, which set off real knock signals. Check coolant level, thermostat operation, water pump, and radiator flow before chasing electrical faults. A failed cooling system can damage far more than a knock sensor if ignored.

Fix: $20–$400 cooling parts
6

PCM Output Driver Failure (Rare)

The PCM's input for the knock sensor circuit can fail, locking the signal line high. Extremely rare — only consider after the sensor, harness, EGR, and cooling system are all verified. Check NHTSA for any PCM reflash TSB before module replacement.

Fix: $0 reflash – $700 PCM

What You'll Need

Tools

  • OBD2 scanner (live data + freeze frame) iCarzone UR800 ›
  • Digital multimeter
  • Socket set (8mm, 10mm, 13mm)
  • Torque wrench (for sensor reinstall)
  • Inspection mirror & flashlight
  • Safety glasses + nitrile gloves

Possible Parts & Supplies

  • OEM knock sensor (e.g., Standard KS225T) $50–$150
  • Knock sensor sub-harness (GM trucks) $30–$80
  • Intake manifold gasket (GM 5.3L: Felpro MS98016T) $30–$80
  • Subaru knock sensor 22060AA180/22060AA18A $80–$130
  • Electrical contact cleaner $5–$10
  • High-temp RTV silicone (GM water dam) $8–$15
Recommended Diagnostic Tool for P0328

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How Do You Fix a P0328 Code?

Follow these steps in order. Use the flowchart below as a quick map of the decision tree — the critical early branch is "real knock vs. circuit fault."

P0328 Diagnostic Flowchart — Decision Tree

P0328 Diagnostic Flowchart Decision tree starting at "Scan codes and capture freeze frame" and branching through real engine knock check, knock sensor connector inspection, sensor resistance test, wiring continuity to PCM, and PCM reflash as a last resort. START · Scan + Freeze Frame Step 2: Listen for actual knock Pinging? Fix octane/cooling/EGR first Real knock? Engine cause first Step 3: Inspect knock sensor connector Corrosion? Water? Clean & reseat Step 4: Test sensor resistance 100–1000Ω · Out of spec? Replace OEM Replaced → Drive Most common fix Step 5: Wiring continuity to PCM Short to 12V? Replace harness Step 6: PCM reflash / replace (rare) Last resort — check NHTSA for free reflash TSB first
Figure 1: P0328 diagnostic decision tree — start at top, work down, exit at the first step that clears the code.
  • 1

    Scan for All Codes and Capture Freeze Frame

    Plug in your scanner and record every stored code. P0328 often appears with companion codes — P0327 (Bank 1 low, sister code), P0332 (Bank 2 low), P0333 (Bank 2 high), or P0420 (catalyst efficiency). Multiple knock-related codes on a V6 or V8 frequently point to a shared wiring harness issue, not two separate sensors. Capture freeze frame data showing RPM, engine load, and coolant temperature when the fault set.

    If both P0328 and P0333 are set together on a V8, the harness is the prime suspect — same wire bundle feeds both sensors and a single short can light both codes.
  • 2

    Check for Real Engine Knock and Overheating

    Before assuming the sensor is bad, rule out an actual knock condition. Drive the vehicle and listen carefully for pinging or rattling under acceleration (especially uphill). Check coolant level and temperature — chronic overheating causes detonation that produces real high-voltage knock signals. Verify you're using the correct octane fuel (e.g., 91+ premium on turbo engines like Subaru WRX, regular on most NA engines). A real knock isn't a sensor fault; it's an engine condition that needs fixing first.

    Important: If you hear distinct metallic pinging or rattling under acceleration, STOP driving hard. Real detonation can crack ringlands and damage rod bearings. Fix the cooling, fuel octane, or EGR issue first; the sensor may be reading correctly.
  • 3

    Locate and Inspect the Knock Sensor Connector

    On most engines the Bank 1 knock sensor threads into the cylinder block on the side where cylinder #1 lives. On 4-cylinder engines it's usually visible on the back of the block. On Toyota V6, Honda V6, and most modern engines, the sensor is reachable from the top. On GM 4.8L/5.3L/6.0L Vortec trucks, the sensors sit in a recess UNDER the intake manifold valley pan — a well-known design weakness where water and coolant pool. Unplug the 2-pin connector and inspect for corrosion, water intrusion, broken pins, or chafed wiring. Spray with electrical contact cleaner.

  • 4

    Test Knock Sensor Resistance and Reference Voltage

    Disconnect the sensor and measure its resistance with a multimeter directly at the sensor pins. Spec varies by engine but is typically 100–1000 ohms for piezoelectric knock sensors at room temperature (verify against your factory service manual). With the key on and engine off, back-probe the signal pin — you should see a 5V reference from the PCM. An open reading (OL/infinite) or a short to ground (near zero) confirms internal sensor failure. Replace with OEM — aftermarket "white box" sensors from eBay/Amazon are notorious for being out of spec from the box.

    A common known-good part on many engines is the Standard Motor Products KS225T (~$100). On GM trucks, use AC Delco or Delphi OEM. On Subaru, use the new design P/N 22060AA180 (Japan) or 22060AA18A (US) — these supersede the older heat-sensitive part.
  • 5

    Check Wiring Continuity Back to the PCM

    If the sensor and connector test good, the fault is in the harness. Disconnect both the knock sensor and the PCM connector, then check continuity of each wire pin-to-pin. Verify the signal wire isn't shorted to the 12V supply — a classic "circuit high" cause. On GM trucks, the knock sensor sub-harness is widely available as a replacement part — install a new sub-harness along with the sensors when the intake is off. Don't reuse a brittle 15-year-old harness even if it tests OK on the bench.

  • 6

    Clear the Code and Verify Spark Timing Returns to Normal

    After any repair, clear all codes and drive through several warm-up cycles plus moderate-load acceleration. Use a live-data scanner to monitor the spark advance PID — with P0328 active, the PCM defaults to a conservative timing map. Once the code is cleared and the sensor reports normal, you'll see timing advance return under load (you'll often feel the throttle response come back). If the code stays clear after 50+ miles, the repair is confirmed.

    If the code returns within a few miles, double-check the harness — many recurring P0328 cases turn out to be a wiring fault that the new sensor can't compensate for.

How Much Does P0328 Cost to Fix?

P0328 costs vary widely by engine layout. On most 4-cylinder and modern V6 engines the sensor is reachable in 30–60 minutes. On GM 5.3L/6.0L Vortec trucks the labor balloons because the intake manifold must come off to reach the sensor.

Repair DIY Cost Shop Cost You Save Type
Connector clean (contact cleaner) $5–$10 $80–$150 Up to $140 Try First
Knock sensor — accessible engine $50–$150 $200–$400 Up to $250 DIY Friendly
Knock sensor — GM 5.3L/6.0L (intake off) $100–$250 $500–$900 Up to $650 DIY Moderate
Sub-harness replacement (GM trucks) $30–$80 +$150 labor — DIY Moderate
Intake manifold gasket (Felpro MS98016T) $30–$80 — — DIY Moderate
Subaru knock sensor (TSB design change) $80–$130 $300–$500 Up to $370 DIY Friendly
EGR valve replacement (if cause) $80–$300 $200–$600 Up to $300 DIY Moderate
PCM reflash (if covered by TSB) N/A (dealer only) $0–$150 — Shop Required
On GM trucks, do the job once: When you have the intake off a 5.3L/6.0L, replace both knock sensors (P0328 + P0333 sister codes), the sub-harness, the intake manifold gasket, and build an RTV dam around the sensor holes. The labor is the same whether you change one sensor or both, and you avoid going back in 6 months.

Per the EPA's emissions standards ↗ EPA Vehicle Emissions I/M Program, a vehicle with an active P0328 code will fail an OBD-II emissions test because the powertrain monitor is incomplete. If your vehicle is under the federal emissions warranty (8 years / 80,000 miles), the knock sensor and PCM may be covered — check with your dealer.

Which Vehicles Are Most Prone to P0328?

P0328 is a generic code that can appear on virtually any modern engine, but two platforms generate the bulk of real-world cases: GM 4.8L/5.3L/6.0L Vortec trucks/SUVs and Subaru 2.0/2.5L boxer engines. We've written dedicated deep-dives for each below the table.

Make Model / Engine Years Primary Cause & Notes Risk
Chevrolet / GMC / Cadillac Silverado, Sierra, Tahoe, Yukon, Suburban, Avalanche, Escalade (4.8L / 5.3L / 6.0L / 6.2L Vortec) 1999–2018 Sensors hidden under intake manifold in a recess that collects water/coolant. GM PIP5576 covers 2014-2018 trucks for related code P0333. See full GM Vortec deep-dive below. High
Subaru WRX, Forester (Turbo & NA), Outback, Legacy, Impreza, Crosstrek, BRZ, Tribeca 2011–2017 Heat-related sensor durability issue. Subaru TSB 07-133-18R introduced new sensor design (P/N 22060AA180 / 22060AA18A). See full Subaru deep-dive below. High
Toyota Camry, Tacoma, Tundra, 4Runner (2.5L L4 / 3.5L V6 / 5.7L V8) 2005–2018 Sensor itself fails after 80,000+ miles. Generally accessible from the top of the engine on V6, less labor-intensive than GM trucks. Medium
Honda Accord, Civic, Pilot, CR-V (K-series L4 / J-series V6) 2003–2017 Knock sensor mounted on the block near the firewall. Replace with OEM Honda parts; aftermarket sensors set false codes. Medium
Ford F-150, Expedition (5.4L / 6.2L V8) 2004–2016 Sensors accessible from the top of the engine but in a heat-stressed location. OEM Motorcraft parts hold up better than aftermarket. Medium
Various VW Jetta, Nissan Frontier, Mazda6, etc. 2000+ P0328 appears at lower rates. Diagnosis is the same: connector → sensor → wiring → PCM. Medium

P0328 on GM 4.8L / 5.3L / 6.0L Vortec V8 (Silverado, Sierra, Tahoe, Yukon — 1999–2018)

The GM Gen III/IV small-block V8 truck and SUV lineup is the most prolific P0328 generator on the road. On these engines, the knock sensors mount in a recess in the valley between the cylinder banks — and the intake manifold seals over that recess. The design flaw: water from washing the engine, condensation, or coolant from a small leak collects in the recess and submerges the sensors and harness. Owners often report P0328 appearing right after a pressure-wash or after a minor coolant weep.

1. Real GM TSB / PIP reference. GM published PIP5576 covering 2014-2018 Silverado 1500, Tahoe, Yukon, Suburban, Escalade, Camaro, and Corvette for the related code P0333 (Bank 2 high) — same family as P0328 and same root cause. Look up your VIN on NHTSA to see if your specific configuration is covered.

2. Required parts. Do the full job once: both knock sensors (AC Delco or Delphi OEM, NOT cheap white-box aftermarket), the knock sensor sub-harness, and the intake manifold gasket (commonly Felpro MS98016T for 5.3L). Budget about $150–$250 in parts plus 3–4 hours of labor.

3. The community-proven water dam fix. After installing the new sensors and harness, build a small dam of high-temp RTV silicone around each sensor's mounting hole on the valley pan. This routes any future water around the sensor holes instead of into them — a fix widely confirmed in GM truck forums and shop reports as preventing recurrence.

GM Vortec action plan: Pull the intake manifold once. Install OEM AC Delco/Delphi knock sensors, a new sub-harness, and the Felpro MS98016T intake gasket. Build RTV silicone dams around the sensor holes before reassembly. This complete job runs about $200 in parts DIY and 3–4 hours of labor — and it's the difference between a permanent fix and chasing the codes back to the shop in 6 months.

P0328 on Subaru Boxer Engines (WRX, Forester, Outback, Impreza, Crosstrek — 2011–2017)

Subaru's 2011-2017 lineup had a documented knock sensor heat durability problem that Subaru addressed via service bulletin. The old sensor design couldn't reliably handle the heat soak around the boxer engine block, and would set P0327 (low) or P0328 (high) codes intermittently — often only after long highway drives or hot-soak parking.

1. Real Subaru TSB. TSB 07-133-18R (revised 11/14/2018) covers a wide model range: 2012-2017 Legacy and Outback, 2012-2016 Impreza, 2013-2017 Crosstrek, 2011-2017 Forester (NA and DIT/Turbo), 2015-2017 WRX, 2013-2017 BRZ, and 2012-2014 Tribeca. The bulletin announces a knock sensor design change introduced into production on November 18, 2016.

2. New part numbers (from the official Subaru bulletin):

  • P/N 22060AA180 — Japan-built vehicles
  • P/N 22060AA18A — SIA / US-built vehicles (Subaru of Indiana plant)

Both numbers reflect the new heat-resistant design (Subaru moved the DIT/turbo-spec sensor over to NA engines because it tolerated heat better). Order based on where your VIN was built, not just by model year.

3. Action plan for Subaru owners. Replace the sensor with the new design P/N. The sensor on most Subaru boxers is accessible from the top of the block — much easier than GM trucks. Plan on 30–45 minutes of labor. If your VIN is in the bulletin's range, contact your Subaru dealer first about whether the repair qualifies for any goodwill assistance before paying out of pocket.

Subaru action plan: Don't replace the sensor with the OLD part number — you'll be back in a year. Confirm via parts catalog or dealer that you're getting the new 22060AA180 / 22060AA18A design that supersedes the heat-sensitive original. Check NHTSA for the latest revision of TSB 07-133-18R before ordering.
How to check for a TSB or PIP: Visit NHTSA.gov ↗, enter your VIN or year/make/model, and filter by Technical Service Bulletins. Search for "P0328," "knock sensor," "P0327," "P0332," or "P0333." Both GM PIP5576 and Subaru TSB 07-133-18R are searchable in this database.

Should You DIY or Call a Mechanic?

DIY If You…
  • ✓ Have an OBD2 scanner with live data & freeze frame
  • ✓ Can use a multimeter to measure voltage and resistance
  • ✓ Have basic hand tools and a torque wrench
  • ✓ Are working on a Subaru or accessible-sensor engine
  • ✓ Want to save $300–$600 in shop labor
Use a Mechanic If…
  • → Vehicle is under emissions or powertrain warranty
  • → Working on a GM 5.3L/6.0L with intake removal required
  • → Audible knock is present (engine cause must be diagnosed)
  • → Code returned after sensor + harness + connector fix
  • → Multiple codes including misfires or O2 sensors
Never authorize valve, piston, or rod bearing work as a first step for P0328. It's an electrical/circuit code on the knock sensor — the engine's internals are almost never the cause. If a shop quotes a bottom-end teardown for a single P0328 code, get a second opinion. Walk through the sensor, connector, harness, EGR, and cooling system first; the typical fix is well under $300.

Related Codes You May See With P0328

P0324
Knock control system error — sister diagnostic on Silverado
P0327
Knock sensor 1 circuit low input (sister to P0328) — generic reference
P0330
Knock sensor 2 circuit malfunction (Bank 2) — generic reference
P0332
Knock sensor 2 circuit low (Bank 2) — generic reference
P0333
Knock sensor 2 circuit high (Bank 2 — GM PIP5576) — generic reference
P0420
Catalyst efficiency below threshold (Bank 1) — generic reference

Frequently Asked Questions

Can I drive with a P0328 code?
Yes, P0328 isn't an immediate safety hazard and the engine will run — but you'll lose 10–20% of fuel economy and noticeable power because the PCM defaults to a conservative spark timing map when it can't trust the knock sensor. If you actually hear pinging or rattling under acceleration, stop driving until you've fixed it: real knock can damage pistons and rod bearings. If there's no audible knock, you can drive for a few weeks while sourcing parts.
Will a P0328 code damage my engine?
Indirectly, possibly. The code itself is electrical and won't damage anything. The risk is if the underlying cause is real engine knock (detonation) that the failed sensor can't report. Without knock feedback, the PCM can't pull timing to protect the engine — so a chronic untreated knock condition can damage pistons over time. Always test-drive listening for pinging before you assume it's just a sensor.
How much does it cost to fix P0328?
Costs range from about $20 (DIY connector clean) to $600+ (shop knock sensor replacement on a GM truck because the intake manifold has to come off). The sensor itself is $20–$150 OEM. On most engines the install is 30–60 minutes. On GM 5.3L/6.0L Vortec trucks plan 3–4 hours because the sensor sits under the intake — and replace the harness, intake gasket (Felpro MS98016T), and both knock sensors while you're in there.
What does the knock sensor do?
The knock sensor is a piezoelectric vibration sensor mounted on or near the engine block. It listens for the high-frequency vibration of detonation (pre-ignition) and reports it to the PCM as a voltage signal between 0.5V and 4.5V. When the PCM detects knock, it retards spark timing to protect pistons. P0328 sets when the signal voltage exceeds about 4.5V for more than 5 seconds — usually because of a failed sensor, a wiring short to power, or real engine knock that's saturating the sensor.
What scanner do I need to diagnose P0328?
You need a scanner with live data and freeze frame — basic code readers can only confirm P0328 is present, not show you the knock sensor PID under load. Watching the sensor voltage rise as you rev the engine is the cleanest way to confirm a stuck-high sensor versus a wiring fault. The iCarzone UR800 is a bidirectional scan tool with live engine data and freeze frame plus full powertrain coverage.
Is P0328 the same as P0327?
They're sister codes on the same circuit. P0327 means Knock Sensor 1 Circuit Low Input — voltage stuck low. P0328 means Circuit High Input — voltage stuck high. Same sensor, opposite electrical failure modes. P0332/P0333 are the same pair for Knock Sensor 2 (Bank 2) on V6/V8 engines. The diagnosis steps are nearly identical, but a "high" code often points to a wire shorted to 12V power, while a "low" code points to an open circuit or ground short.
What causes P0328 on a Chevy Silverado or GMC Sierra 5.3L?
On GM 4.8L/5.3L/6.0L Vortec engines, the knock sensors sit in a recess under the intake manifold, exposed to water and coolant pooling. The harness corrodes and the sensors fail prematurely — especially after a pressure-wash or coolant leak. GM published PIP5576 covering 2014-2018 Silverado/Tahoe/Yukon/Suburban for related code P0333. Fix requires removing the intake manifold, replacing both sensors with OEM AC Delco/Delphi parts, replacing the sub-harness, and building an RTV silicone dam around the sensor holes to prevent water intrusion. See our GM Vortec deep-dive above.
What causes P0328 on a Subaru WRX or Forester?
Subaru's turbo and NA boxer engines had a knock sensor heat durability issue that Subaru addressed with TSB 07-133-18R. The bulletin covers 2012-2017 Legacy/Outback, 2012-2016 Impreza, 2013-2017 Crosstrek, 2011-2017 Forester (NA and Turbo), 2015-2017 WRX, 2013-2017 BRZ, and 2012-2014 Tribeca. New part numbers are 22060AA180 (Japan-built) and 22060AA18A (SIA/US-built). If your VIN is on the affected list, check whether Subaru will assist under goodwill before paying out of pocket. See our Subaru deep-dive above.
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Our team of ASE-certified technicians and OBD-II diagnostic engineers review every article for technical accuracy. Content is based on hands-on diagnostic experience across domestic, Asian, and European vehicle platforms.

10+ years diagnostic experience ASE Certified Last reviewed: May 2026