P0332 on a Buick is "Knock Sensor Circuit Low, Bank 2." It only applies to Buicks with a second knock sensor — and that list is longer than many guides assume. GM's own monitor tables show a second sensor, with its own P0332 test, on the 3800 V6 from 2000 on, the 3.6L V6 in the Enclave, LaCrosse and Regal, the Northstar Lucerne, the 5.3L V8 Rainier and LaCrosse Super — and, unexpectedly, the 4.2L inline-six Rainier, where "bank 2" simply means sensor 2. On the 1.4L turbo Encore, GM lists only one sensor. Whatever the engine, P0332 is an electrical code, not a sign your engine is knocking, and the wiring is the first suspect.
Jump to a section: What P0332 means · Which Buicks have a bank 2 sensor · What GM's monitor checks, by engine · Which side is bank 2 · Symptoms · Causes and how to confirm each · How it's diagnosed · Parts and cost · GM documents · What other pages get wrong · FAQ
What Does P0332 Mean on a Buick?
A knock sensor is a piezoelectric sensor bolted to the engine block. It listens for detonation — fuel igniting too early or too violently — and the engine computer pulls spark timing back when it hears it.
Buicks with two knock sensors use one per bank (or, on the inline-six, one per half of the engine). GM's codes for the second sensor are:
- P0330 — Knock Sensor Circuit, Bank 2
- P0331 — Knock Sensor Performance, Bank 2
- P0332 — Knock Sensor Circuit Low, Bank 2
- P0333 — Knock Sensor Circuit High, Bank 2
Their bank 1 mirrors are P0325, P0326, P0327 and P0328. See our P0325 Buick guide for sensor 1.
"Low" means the computer saw the sensor circuit voltage fall below the range it expects. That usually means a wire shorted toward ground, a damaged connector or a pinched harness — and only sometimes the sensor itself.
While the circuit is faulted, the computer cannot trust what it hears from that sensor, so it typically runs more conservative spark timing. That is the source of the sluggish feel and lost fuel economy some owners notice.
Which Buicks Have a Bank 2 Knock Sensor
GM publishes the logic behind every emissions code in its OBD summary tables. We read those tables across the Buick engine line to confirm which engines carry a P0332 test.
| Buick engine | Typical Buick models | P0332 in GM's tables? |
|---|---|---|
| 3800 V6 (L36, L67, L32, L26) | LeSabre, Park Avenue, Regal (to 2004), LaCrosse and Allure (2005–2009), Lucerne CX | Yes — "a wiring fault with knock sensor 2" (supercharged L67 from 1999; the 3.8L groups from 2000; the 2008 L26 group) |
| 3.6L V6 (LY7, LLT, LFX, LFY, LGX) | Enclave, LaCrosse, Allure, 2018–2019 Regal GS | Yes — 2008 and 2014 tables |
| 4.6L Northstar (LD8) | Lucerne CXS and Super | Yes — 2008 table |
| 5.3L V8 (LH6, LS4) | Rainier, LaCrosse Super | Yes — GM V8s carry one sensor per bank |
| 4.2L inline-six (LL8) | Rainier | Yes — GM lists P0330–P0333 "for LL8" |
| 1.4L turbo (LUJ, LUV) | Encore | No — the 2014 table lists knock codes for sensor 1 only |
| Other four-cylinders (2.0T, 2.4L, 2.5L, 1.2T/1.3T, 1.5T) | Regal, Verano, LaCrosse, Envision, Encore GX, Envista | We could not confirm per engine — GM's tables group these with engines that do have two sensors |
One note on the 3800: GM's 1998 and 1999 tables for the non-supercharged L36 do not list knock sensor codes at all. If you have a late-1990s LeSabre or Park Avenue, check whether P0332 is even supported on your year before chasing it.
Tools for testing the knock sensor circuit
FOXWELL NT726 Bidirectional Scanner
$368.99Bidirectional scan tool for knock retard and all-module codes.
ACDelco 2-Pin Replacement Connector PT3739
$90.99Two-pin replacement connector for a corroded sensor pigtail. Confirm fitment by VIN before ordering.
FOXWELL BC521 Battery Charger & Tester
$162.35Charger and tester for battery health.
What GM's Monitor Checks, by Engine
The code number is the same across Buicks, but GM changed the test over the years. Knowing which version your engine uses tells you what kind of fault to look for.
| Engine | What GM's P0332 monitor checks | What that means |
|---|---|---|
| 3800 V6 | Knock sensor 2 output amplitude is low and stays relatively constant (average below 4.8 V), on a warm engine (ECT ≥ 60 °C) between 1,000 and 2,500 rpm, throttle at least 10% and load at least 40% | GM calls this "a wiring fault with knock sensor 2" — a flat, dead signal |
| 2008-era 3.6L LY7, 4.2L LL8, Northstar | Sensor signal line above about 2.86 V or return line below about 1.48 V | The bias on the circuit has been pulled out of range — wiring or connector |
| 2014-on 3.6L (LFX, LLT and later) | Sensor input or return below 8% of the 5-volt reference | A short toward ground or a low-resistance path in the wiring |
GM lists P0332 as a Type B code on these engines, so the check engine light normally comes on after the fault shows up on two drive cycles.
The common thread: every version of P0332 is looking at the circuit. None of them is a measurement of actual engine knock.
Which Side Is Bank 2?
On GM V6 and V8 engines, bank 1 is the bank that contains cylinder 1, and bank 2 is the other one.
- 3.6L V6 Buicks (Enclave, LaCrosse, Regal): GM defines bank 1 as the right side viewed from the flywheel end, which on these transverse engines is the rear, firewall-side bank. That makes bank 2 the front bank, toward the radiator.
- 5.3L V8 (Rainier, LaCrosse Super): GM V8 bank 1 is the driver side, so bank 2 is the passenger side.
- 4.2L inline-six (Rainier): there is only one bank. GM's tables simply label the second knock sensor's codes "bank 2."
- 3800 V6: GM's tables call it knock sensor 2. Use the GM service information for your model to locate it — we did not confirm the 3800 sensor locations in a GM document.
Finding the right sensor matters: on several of these engines one sensor is far easier to reach than the other, and replacing the wrong one costs labor and fixes nothing.
Symptoms of P0332
- Check engine light on
- Reduced power or sluggish acceleration from conservative spark timing
- Lower fuel economy
- Frequently no noticeable symptom at all
- Audible spark knock under load in some cases, especially on lower-octane fuel
- P0327 set alongside if wiring shared by both sensors is damaged
Causes and How to Confirm Each
| Cause | How to confirm it | Notes |
|---|---|---|
| Wiring shorted toward ground | Circuit tests for short to ground on the signal and return lines | The 2014-on 3.6L test is a bias-voltage check — wiring is the prime suspect |
| Chafed or pinched harness | Inspect along the routing, especially where it passes brackets, pulleys or the intake | Look closely after any intake, plug or harness work |
| Connector or terminal fault | Inspect the sensor and ECM connectors for corrosion, moisture and pin tension | Engine washing and leaks can let water in |
| Rodent damage | Visual inspection of the engine harness | Common on vehicles that sit |
| Sensor loose or incorrectly torqued | Check mounting torque against GM specification | On the 3800, a flat, quiet signal is exactly what GM's test looks for |
| Failed knock sensor | Only after wiring and connectors test good | Order by VIN |
Parts for the wiring and sensor causes
Nomex Split Loom, 1 in. x 10 ft
$105.66Heat-resistant split loom for re-protecting a repaired harness.
GM Genuine 12589867 Knock Sensor
$66.15GM Genuine knock sensor — replace only after the circuit tests good. Confirm fitment by VIN before ordering.
How Is P0332 Diagnosed on a Buick?
- Confirm the engine has a second sensor. If your Buick is a 1.4L Encore or a late-1990s non-supercharged 3800, check that the code is valid for your engine.
- Record all codes. P0332 alone points to sensor 2's circuit; P0327 and P0332 together point to wiring both sensors share.
- Identify bank 2 on your engine using the notes above and the GM service information.
- Ask about recent work. Intake manifold removal, rear spark plug service or harness repairs are common triggers.
- Inspect the connector and harness from the sensor to the ECM.
- Test the signal and return circuits for a short to ground and for continuity per the wiring diagram.
- Replace the sensor only after the wiring tests good, and torque it to GM's specification.
- Clear the code and drive under the monitor's conditions — on a 3800, a warm engine between 1,000 and 2,500 rpm under moderate load.
Parts and Cost
| Repair | What it involves | Cost picture |
|---|---|---|
| Harness or connector repair | Repair the chafed section, re-secure the harness, or fix the terminal | Usually the real fix — and the cheapest |
| Knock sensor, accessible location | Sensor and torque to specification | Modest |
| Knock sensor under the intake or behind other components | Intake removal or significant disassembly, new gaskets | Labor-heavy — the part is the small part of the bill |
| Sensor replaced for a wiring fault | What happens when "knock sensor code" is read as "knock sensor part" | Money spent with the fault still present |
If you replace a sensor, order it by VIN and torque it to specification. An overtightened or undertightened knock sensor does not hear the block correctly and can set codes of its own.
For the sensor replacement
Intake Manifold Gasket Set, 2010–2017 3.0L/3.6L
$27.99Intake gasket set for 2010–2017 3.0L/3.6L V6s. Confirm fitment by VIN before ordering.
ACDelco 10-2010 RTV Engine Sealant
$22.35GM RTV engine sealant.
ACDelco Digital Torque Wrench, 3/8 in. (5–99.5 ft-lb)
$249.99Torque the knock sensor to spec — a loose sensor reads wrong.
GM Documents for P0332 on Buick Models
We found no GM service bulletin that names P0332 for a Buick model. The well-known GM P0332 bulletins — PIT5307 for the vacuum pump pulley harness chafe and 02-06-04-023 for corroded rear sensors — cover Chevrolet, GMC and Cadillac trucks, not Buicks, so we do not cite them for your Buick. They are explained in our Chevrolet P0332 guide. The documents below are GM's own monitor definitions for Buick engines.
| Document | Subject | Status |
|---|---|---|
| GM OBD summary tables, 3800 V6 (1999 L67; 2000–2006 3.8L groups; 2008 L26 group) | P0332 detects a wiring fault with knock sensor 2 — low, constant amplitude on a warm engine, 1,000–2,500 rpm | Buick 3800 applications incl. Lucerne, LaCrosse, Allure — verified |
| GM OBD summary tables, 2008 groups 03, 09, 12a, 13 | P0332 sets with signal line above about 2.86 V or return below about 1.48 V; LL8 entries marked "for LL8" | 3.6L LY7 Enclave/LaCrosse, 4.2L LL8 Rainier, 4.6L Northstar Lucerne — verified |
| GM OBD summary table, 2014 group 06A | P0332 sets when sensor input or return is below 8% of the 5 V reference; Type B, two trips | 3.6L LFX/LLT Enclave and LaCrosse — verified |
| GM OBD summary table, 2014 group 02 | Knock codes listed for one sensor only | 1.4L LUV/LUJ Encore — verified |
| PIT5307F (2019) | Engine harness chafing at vacuum pump pulley; DTCs include P0332 | Chevrolet/GMC/Cadillac trucks only — verified, not a Buick |
Have a dealer check your VIN against current bulletins rather than relying on any article, including this one.
What Other P0332 Pages Get Wrong
- "P0332 means your engine is knocking." Every version of GM's P0332 test checks the circuit. The engine may be perfectly healthy.
- "The 3800 only has one knock sensor." GM's tables for the 3800 from 2000 on — and the supercharged L67 from 1999 — include a P0332 test described as a wiring fault with knock sensor 2.
- "An inline-six can't set a bank 2 code." GM's tables list P0330–P0333 for the Rainier's 4.2L LL8. "Bank 2" there means sensor 2.
- Copying truck bulletins. PIT5307 is a real GM fix for P0332 — on Silverados and Tahoes. It does not cover any Buick.
- Replacing the sensor first. "Circuit low" usually means wiring. Test it before buying parts.
Frequently Asked Questions
Is it safe to drive with P0332?
Usually yes in the short term — the computer typically retards timing to protect the engine when it cannot trust a knock sensor. Expect reduced power and economy, use the fuel your owner's manual specifies, and avoid heavy loads until it is fixed.
Which side is bank 2 on my Enclave?
On the transverse 3.6L V6, bank 1 is the rear, firewall-side bank, so bank 2 is the front bank toward the radiator. Confirm the sensor location in GM service information before removing parts.
Can my Encore set P0332?
GM's 2014 tables for the 1.4L turbo list knock codes for one sensor only. If a scan tool shows P0332 on a 1.4L Encore, re-check the code and the tool before diagnosing.
What's the difference between P0332 and P0333?
Low versus high. P0332 means the circuit voltage dropped too low — usually a short toward ground. P0333 means it went too high, which GM tests separately and usually points to a different wiring fault.
Why do I have P0327 and P0332 together?
Both sensors' circuits are low at once. That points to damage in wiring both share, or a connector problem, rather than two sensors failing together.
Does premium fuel fix P0332?
No. P0332 is an electrical fault. Using the fuel grade GM specifies is still wise while the knock system is impaired.
Shop Related Parts & Tools
“Circuit low” usually means wiring — test the harness and connector before buying a sensor. Order sensors by VIN and torque them to GM's specification.
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ACDelco Knock Sensor 213-92 (Buick, Cadillac, Chevy, GMC) — a GM original-equipment knock sensor listed for Buick and other GM applications; confirm fitment against your VIN and replace it only after the wiring tests good.
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Launch CRE 2.0 GM All-System Scanner — a GM all-system scanner that shows GM's knock sensor descriptors for both banks.
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FOXWELL NT301 OBD2 Scanner — reads P0332 alongside P0327 so you can tell whether shared wiring is involved.
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95-Piece Mechanics Tool Set (Metric & SAE) — for harness, connector and sensor access.