P0303

What P0303 means

Same misfire diagnosis, isolated to cylinder #3.

Vehicle-specific P0303 guides

P0303 can mean different things on different vehicles. Pick your make for engine-family specifics:

Symptoms

• CEL
• Rough idle
• Loss of power

Likely causes (most common first)

1. Coil
2. Plug
3. Injector
4. 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 P0303 typically run up to $800 depending on the underlying cause and vehicle. Start with the most common cause — Coil — before throwing parts at it.

Symptoms that match P0303

If you got here from a search query, one of these might describe what your car is actually doing:

• Check Engine Light Flashing — What It Means and What to Do
• Engine Misfire — Symptoms, Codes, and What to Fix First
• Rough Running on Cold Start — Causes and Fixes

Recommended parts & tools for P0303

Compare the parts and tools that pair with AXLY:

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Related codes

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