What causes the P0304 misfire detected in cylinder 4?
2 Answers
P0304 primarily indicates a misfire detection in cylinder 4. The main causes of this phenomenon include no ignition in cylinder 4, no fuel injection in cylinder 4, or insufficient cylinder pressure in cylinder 4, etc. The first step is to inspect the intake and exhaust systems, ignition system, and fuel supply system. Identifying the faulty component and replacing it will resolve the issue. Below is an introduction to automotive fault codes: 1. Introduction one: Automotive fault codes are codes reflected by the vehicle's computer ECU after analyzing a fault issue. Most fault codes are caused by sensor malfunctions or poor sensor performance, but some mechanical faults cannot be read by the ECU. 5. Introduction two: When there is an issue with the car engine, the diagnostic computer will display fault codes after inspection. Using these codes, repair personnel can accurately locate the faulty component and proceed with repairs. 3. Introduction three: Automotive fault codes can be divided into two types: intermittent faults and actual faults.
I've been driving for over a decade, and I've seen the P0304 cylinder 4 misfire code quite often. The main issue could be with the spark plugs, like if the gap is too wide or there's too much carbon buildup, which affects ignition. Another possibility is a faulty ignition coil—if it's broken, it can't power the spark plug, causing the cylinder to misfire. Other causes include clogged fuel injectors, preventing fuel from spraying, or insufficient engine compression due to worn piston rings or valve leaks. Wiring connections can also be problematic, like loose spark plug wires or faulty sensor signals. I'd recommend starting with simple checks, like replacing the spark plugs yourself. If that doesn't work, take it to a shop to test the compression pressure. Don't delay, or the car will shake badly, fuel consumption will spike, and it could damage the catalytic converter.
