P0302 on Suzuki: How to Diagnose & Fix
Cylinder 2 Misfire Detected
1 Suzuki model · 1 documented issue · $200-$1,200 repair
P0302 on Suzuki by model: symptoms, diagnosis and fix
The K10B 1.0 3-cylinder in Alto, Celerio (early), Splash, and Wagon R uses shim-under-bucket valve adjustment — not the more common hydraulic lash adjusters. Suzuki specifies a check at 96,000 km but many owners (and dealers) skip it; tight valves over time cause burned exhaust valves and failed compression.
Common Symptoms
- rough idle
- misfire
- low compression
- reduced economy
How to Fix
Valve clearance check + adjustment at 96,000 km is in the service book — confirm it has been done. £200-£400 labor + shims. If skipped repeatedly, eventually a leak-down test will reveal valve burn — head rebuild £700-£1,200.
P0302 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 P0302 mean on a Suzuki?
P0302 stands for "Cylinder 2 Misfire Detected." This code means the engine computer has detected a misfire specifically in cylinder 2, meaning that cylinder isn't completing combustion properly on some firing events. The computer watches tiny variations in crankshaft speed to spot when a cylinder fails to fire, and a misfire means the air-fuel mixture isn't igniting correctly — usually from a spark, fuel, or compression problem in that cylinder. You may feel a stumble, rough idle, shaking, loss of power, or a flashing check-engine light, and persistent misfires can damage the catalytic converter. Because it names a single cylinder, the fault is often a component serving just cylinder 2, like its coil, plug, or injector. On Suzuki it is documented across 1 model: Alto.
What are the most common causes of P0302?
The most common causes of P0302 are: Worn or fouled spark plug (cylinder 2), Failed ignition coil or coil-on-plug (cylinder 2), Clogged or faulty fuel injector (cylinder 2), Vacuum or intake air leak affecting that cylinder, Low compression (worn rings, burnt/bent valve, head gasket), Damaged spark plug wire or boot (if equipped), Carbon-tracked or cracked coil/plug causing spark loss, Faulty PCM/ECM driver (rare). The specific cause varies by vehicle.
How much does it cost to fix P0302 on a Suzuki?
Published repair estimates on Suzuki range from $200 to $1,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0302 on a different make?
View P0302 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.