P0303 means cylinder 3 misfire detected. Cylinder 3 isn't firing properly. Diagnosis is straightforward since the computer isolated the cylinder — check its plug
Drive gently and get it diagnosed within days.
Cylinder 3 isn't firing properly. Diagnosis is straightforward since the computer isolated the cylinder — check its plug, coil, and injector first.
Most common cause.
Heat-cycled coils fail with age.
Cylinder 3 fuel starvation.
Valve or ring wear.
Damaged connector or harness.
Typically $100–$500
Single plug/coil typically $100–$300; injector work typically $150–$400. Estimates vary by vehicle. Costs are estimates and vary by vehicle, location, and shop.
Short drives are fine; don't ignore it — the catalytic converter is at risk from unburned fuel.
Typically $100–$500. Single plug/coil typically $100–$300; injector work typically $150–$400. Estimates vary by vehicle.
Drive gently and get it diagnosed within days.
The most common cause is worn spark plug in cylinder 3. Most common cause.