Is it safe to drive with a P0304 code?

Severity is high. Address P0304 sooner rather than later — driving with an active check engine light can worsen the problem or void emissions warranties.

How much does it cost to fix P0304?

Repair costs for P0304 typically range from $40 to $800 in the US, depending on the underlying cause. The most common fix is: Coil.

What are the symptoms of P0304?

CEL. Rough idle. Loss of power.

Check Engine Code

P0304

Cylinder 4 Misfire Detected

Severity: high DIY difficulty: 2/5 Typical cost: $40–$800

What P0304 means

Same misfire diagnosis, isolated to cylinder #4.

Symptoms

CEL
Rough idle
Loss of power

Likely causes (most common first)

Coil
Plug
Injector
Compression

Can I keep driving?

High — risk of damage if ignored

Typical repair cost

DIY fixes can start near $40 (parts only). Shop repairs for P0304 typically run up to $800 depending on the underlying cause and vehicle. Start with the most common cause — Coil — before throwing parts at it.

Related codes

P0300 P0301 P0302 P0303

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