P0324 on Chevrolet: How to Diagnose & Fix
Knock Control System Error
1 Chevrolet model · 1 documented issue · 1 critical
P0324 on Chevrolet by model: symptoms, diagnosis and fix
GM issued urgent dealer message DCS6982 on August 14, 2024 covering 2024 vehicles with the 1.2L gasoline engine - Chevrolet Trax and Trailblazer, Buick Encore GX and Envista. The engine control module may fail to properly control ignition timing following certain Auto Engine Stop/Start restart events. When that happens the malfunction indicator lamp comes on and the engine runs rough or audibly knocks; GM's own bulletin warns that continuing to drive with the knock present can cause engine damage. The matching service bulletin, 24-NA-064, directs technicians to reprogram the ECM when the MIL is set with DTC P0324 (knock control system error) and/or P0116 (engine coolant temperature sensor performance). Because detonation on a small-displacement turbo three is exactly the loading that hurts rod bearings, this is worth chasing promptly rather than living with.
Common Symptoms
- Check engine light after an Auto Stop/Start restart
- Audible engine knock or detonation rattle
- Rough running after the engine auto-restarts
- Hesitation pulling away from a stop
How to Fix
Free remedy - the dealer reprograms the Engine Control Module with updated calibration; no parts are required. Reference GM message DCS6982 and bulletin 24-NA-064 when booking. If the knock persists after the reflash, insist on a borescope and an oil-analysis/bearing inspection rather than accepting 'normal three-cylinder noise'. In the interim you can reduce exposure by switching Auto Stop/Start off at each start and running top-tier 87-octane or better fuel.
Sources for this issue (2)
P0324 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0324 mean on a Chevrolet?
P0324 stands for "Knock Control System Error." The PCM has detected an internal fault or an implausible input within the knock-control system. The knock control system uses one or more knock (detonation) sensors to listen for combustion knock/ping and lets the PCM retard ignition timing and adjust fueling to prevent detonation. P0324 sets when the module receives an unexpected knock-sensor signal (for example the circuit reading battery voltage, a full ground, or constant electrical noise) or when the internal knock-processing self-test fails, so the PCM can no longer trust its knock detection. Losing knock control can allow damaging detonation and typically causes the PCM to pull timing as a protective default. On Chevrolet it is documented across 1 model: Trax.
What are the most common causes of P0324?
The most common causes of P0324 are: Failed knock (detonation) sensor, Damaged, corroded, or loose knock sensor wiring, connector, or terminals, Short to voltage or short to ground in the knock sensor circuit, Excessive engine mechanical noise mimicking knock (worn components) confusing the system, Internal PCM / knock-processing fault, or PCM needing a software update. The specific cause varies by vehicle.
How much does it cost to fix P0324 on a Chevrolet?
Repair costs vary widely with the root cause and Chevrolet model; each issue on this page carries its own estimate where one is published.
Looking for P0324 on a different make?
View P0324 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.