Cylinder 2 Misfire Detected
In short
P0302 means the engine's computer detected a misfire on cylinder 2, where the air-fuel mixture failed to ignite properly or didn't combust completely. The most common real-world cause is a worn spark plug or a failing ignition coil on that specific cylinder. Because the fault is tied to one cylinder, swapping the coil or plug from a neighboring cylinder to see if the misfire follows is the fastest way to confirm the source.
Is it safe to drive with P0302?
Short trips at light load are usually okay, but a steady or worsening misfire is not safe to ignore. Unburned fuel passing into the exhaust can overheat and damage the catalytic converter, and a flashing check-engine light means active misfire that warrants stopping and reducing engine load. Avoid hard acceleration and get it diagnosed within a day or two.
Symptoms
- Rough idle or noticeable shaking, especially at a stop
- Check-engine light on, or flashing during active misfire
- Hesitation, stumble, or lack of power on acceleration
- Reduced fuel economy
- Occasional popping or sputtering from the exhaust
- A faint raw-fuel or rotten-egg smell from the tailpipe
Common causes (most → least likely)
How to diagnose it (before buying parts)
- 1 Scan for all stored codes and freeze-frame data — note whether other misfire codes (P0300, P0301, etc.) or lean/rich codes are present, since multiple codes change the diagnosis.
- 2 Visually inspect the cylinder 2 coil connector, wiring, and boot for damage, oil, water, or corrosion, and check for obvious vacuum leaks.
- 3 Swap the cylinder 2 ignition coil with an adjacent cylinder, clear the code, and drive — if the misfire moves to the new cylinder, the coil is the fault.
- 4 Pull and inspect the cylinder 2 spark plug for wear, fouling, oil, or cracked porcelain; compare it against the other plugs.
- 5 If ignition checks out, test for fuel and compression on cylinder 2 — verify injector operation (resistance/noid or balance test) and run a compression or leak-down test before buying major parts.
Repair options & cost
By manufacturer
Coil-on-plug failures are a frequent single-cylinder misfire cause; replacing one often-fragile coil is a common fix, though doing the whole set on higher-mileage engines prevents repeat visits.
On modular V8s and EcoBoost engines, coil-on-plug units and worn plugs are typical single-cylinder misfire culprits; on older 4.6/5.4 engines, check for blown-out or damaged plug threads.
Generally robust ignition, but aging ignition coils and plugs past their service interval drive isolated misfires; carbon buildup on direct-injection engines can also contribute.
TSI/TFSI engines are well known for ignition coil failures causing single-cylinder misfires; coils are often replaced as a set, and carbon buildup on intake valves can aggravate misfires.
Frequently asked questions
Can I drive with a P0302 code?
For a short distance at light load, usually yes, but you shouldn't keep driving on it. A persistent misfire dumps unburned fuel into the exhaust and can ruin the catalytic converter, an expensive repair. If the check-engine light is flashing, reduce load and get it fixed right away.
Which cylinder is cylinder 2?
Cylinder numbering depends on the engine and manufacturer, so cylinder 2 is not always the second one you see. Check a firing-order or cylinder-layout diagram for your specific engine, or consult the service manual, to locate it correctly before working.
How much does it cost to fix a P0302?
Most P0302 repairs are inexpensive: a spark plug or single ignition coil typically runs about 50 to 300 dollars including labor at a shop, and far less for DIY. Costs climb only if the cause is a fuel injector or internal mechanical problem like low compression.
Will a misfire clear itself once I fix the part?
The misfire stops as soon as the faulty component is replaced, but the stored code and check-engine light may need to be cleared with a scan tool or will reset after several drive cycles. If the light returns, the underlying cause was not fully addressed.
Related codes
Sources and model caveats
Code behavior and repair procedures can vary by engine, model year and calibration. Confirm the diagnosis against the vehicle's service information before replacing parts.
- Manufacturer service information
- Field diagnostic experience — replace with cited, verifiable references before publishing