Common symptoms
The P0304 cylinder misfire code can result from a combination of ignition system issues. So, it’s essential to identify its symptoms to get to the root cause of this p-code.
You may encounter generic trouble code symptoms like the check engine light, along with a few others, every time you get this trouble code.Â
Here are some of those symptoms:Â
1. Reduced Engine PerformanceÂ
A faulty ignition system (including a bad coil, coil pack, a damaged ignition wire, or cylinder head) can negatively affect engine performance and cause rough idle, engine noise, etc.
As a result, you will experience reduced engine performance, including issues with fuel efficiency.Â
2. Smell Of Raw Fuel From The Exhaust
In this case, the smell of raw fuel indicates excess, unburnt fuel in the cylinder 4. It could be due to an inoperable ignition coil or coil pack, a faulty fuel pump, or a worn fuel filter.
Whatever the case, it needs immediate attention to prevent a cylinder 4 misfire.Â
3. Hesitant Acceleration
If your cylinder 4 misfire results from a faulty spark plug or damaged plug wire, your engine will experience a loss of power due to incorrect combustion of the air-fuel mixture.Â
You may need to get a new plug and have your spark plug wires changed.
4. Illuminated Check Engine Light
A lit check engine light is one of the most common symptoms of code P0304. However, your car’s engine light may also indicate p-codes pertaining to the ignition system, fuel pressure, or other engine components.
So it’s best to let your mechanic handle the troubleshooting using professional tools that will accurately identify the trouble code. They may also do a compression test to isolate the root cause of p-code P0304.Â