P0304 Volkswagen Code - Cylinder 4 Misfire Detected
Quick Answer
When a misfire occurs, engine speed will fluctuate. Common causes include Faulty Spark Plug #4, Clogged or faulty Fuel Injector #4, Faulty Ignition Coil #4. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0304 Volkswagen indicates Cylinder 4 Misfire Detected.
- Common causes
- Common causes include Faulty Spark Plug #4, Clogged or faulty Fuel Injector #4, Faulty Ignition Coil #4.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P0304 Volkswagen Description
What are the Possible Causes of the DTC P0304 Volkswagen?
- Faulty Spark Plug #4
- Clogged or faulty Fuel Injector #4
- Faulty Ignition Coil #4
- Fuel Injector #4 harness is open or shorted
- Fuel Injector #4 circuit poor electrical connection
- Ignition Coil #4 harness is open or shorted
- Ignition Coil #4 circuit poor electrical connection
- Insufficient cylinder 4 compression
- Incorrect fuel pressure
- Intake air leak
How to Fix the DTC P0304 Volkswagen?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0304 Volkswagen code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0304 Volkswagen Code
1. What are common symptoms of OBDII code P0304 in a Volkswagen?
Common symptoms include engine misfires, rough idling, loss of power, and increased fuel consumption.
2. What are the possible causes of a Cylinder 4 misfire in a Volkswagen?
Possible causes include faulty spark plugs, ignition coils, fuel injectors, vacuum leaks, or low compression in the cylinder.
3. How can I diagnose the cause of a Cylinder 4 misfire in my Volkswagen?
Diagnostic steps may include checking spark plugs, ignition coils, fuel injectors, compression levels, and performing a visual inspection for any obvious issues.
4. Can driving with a misfiring Cylinder 4 cause damage to my Volkswagen?
Continued driving with a misfire can potentially damage the catalytic converter, oxygen sensors, and other engine components, leading to more expensive repairs.
5. How can I repair a Cylinder 4 misfire in my Volkswagen?
Repairs may involve replacing faulty spark plugs, ignition coils, fuel injectors, or addressing any vacuum leaks or compression issues in Cylinder 4.
6. Is it safe to drive my Volkswagen with OBDII code P0304 present?
It is not recommended to drive with a misfire as it can cause further damage to the engine and emissions system. It's best to address the issue promptly.
7. Can bad gasoline cause a Cylinder 4 misfire in a Volkswagen?
Low-quality or contaminated gasoline can contribute to misfires, so it's advisable to use fuel from reputable sources to prevent such issues.
8. Are there any maintenance tips to prevent Cylinder 4 misfires in a Volkswagen?
Regularly scheduled maintenance, such as replacing spark plugs and ignition components as recommended by the manufacturer, can help prevent misfires.
9. Does weather or temperature affect the likelihood of a Cylinder 4 misfire in a Volkswagen?
Extreme weather conditions, such as very low temperatures, can sometimes exacerbate existing issues that may lead to misfires, so it's important to maintain your vehicle accordingly.
10. Should I reset the OBDII code P0304 after repairing the issue in my Volkswagen?
After addressing the cause of the misfire, it's recommended to clear the error code using an OBDII scanner to reset the system and see if the issue has been resolved.
Discuss the causes and fixes for P0304 Volkswagen OBDII Code
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Someone please help. I have a 2005 VW Bug 2.0 liter and the same codes keep popping up. Random cylinder misfire and number four cylinder misfire. I have changed the coil, the plug's and wire's, checked for air intake leak and it still has the same codes every time I clear them.
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Next step is to perform a compression test to check the head gasket. It's somewhat common for the 05 Bug to have problems with the head gasket.
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I have a 04 vw jetta 2.0 and the computer is telling me that cylinder 4 misfire detected and it says po304
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You should start by changing the spark plugs. If the problem persist, you could have a bad ignition coil or fuel injector.
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I have a 2011 Tiguan giving p0304 only on cold mornings. Swapped ignition coils 3&4. Also ran Techron through it. Any thoughts?
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Check the spark plugs. You could swap spark plugs and test again, but if the problem persist, you probably have a bad fuel injector.
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98 years VW Golf 1.4 16v begins to warm the engine idling FUME although acceleration is good.
Whats problem engine.
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Hello ive a vw golf 2.0fsi ive been experiencing rough idle and have had a random misfire across all 4
Changed spark plugs,coils, 3 coil connectors and the cam follower oil and filter changed and coolant topped up
After sticking her back together and starting her back up the engine seemed to run alot better pulls better through the 6speed box and accelerates well but today again P0304 came back at least im down to one cylinder now. Engine detox booked for tomorrow, only causes left are -intake air leak that i cant see,
-blocked or faulty injector 4
-injector 4 poor eletrical connection
-injector 4 harness Open or shorted -incorrected fuel pressure
-insufficent pressure in cylinder 4 -
A good trick to diagnose your self is to change 3&4coil and 2&4 spark plug if your issue moves to either cylinder you can tell which part is the issue same on fuel injectors before spending money on a part that may not change anything go ahead and swap then about if your issue moves along with the part you changed then you have a good idea about the underlying issue or issues
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https://youtu.be/dWEq_qNZffg
check this video out it will help diagnose this issue.
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