Here is my list of symptoms:
Code P0304:
•A recurring Check Engine Light code indicating a specific cylinder misfire in Cylinder 4.
•The issue has persisted for over 1 year, always returning to the exact same cylinder despite parts being replaced.
•The Check Engine Light intermittently turns off on its own after a few smooth drives.
•Most recent scan at Valvoline detected a PERMANENT P0304 code.
Rapid Oil Loss:
•The engine oil has recently started draining and consuming much faster between services without leaving a visible puddle on the ground.
•My engine oil is halfway between Full and Low, yet it has been less than 2,000 miles since my last oil change.
Engine Ticking:
•A distinct metallic ticking noise coming from the engine that started about a year ago and has progressively worsened. It subsides after the engine warms up.
Metal on Sensor:
•An independent inspection by Christian Brothers Automotive physically discovered a metallic debris coating the magnetic crankshaft sensor which caused it to be damaged.
•Mechanic noted that there was no damage to the flex plate teeth.
Rough Starts:
•Intermittent, violent shaking and rough idling immediately upon starting the vehicle when the engine is COLD.
Acceleration:
•Car will not go past 2,500 RPM.
•Car will intermittently ‘fall back’ in power during acceleration. I can feel it physically when driving.
Constant Idle Vibration:
•A slight, continuous vibration felt through the car whenever the vehicle is turned on and idling.
A/C Shudder:
•When the A/C is turned on and the car is idling at a stoplight or in park, the engine experiences a sudden hiccup that feels like a shudder coming from the front hood.
•The A/C shudder has triggered a severe, uncontrollable shaking and jerking of the entire vehicle on a few occasions.
I took my car to the Kia dealership yesterday and they seem intent that this is all based on a bad fuel injector. They said they won't take into account the metallic debris on the crankshaft sensor because they didn't do the repair. I brought the car in to them back in March for the same recurring issues. They said it was bad spark plugs and 2 bad coils, which I had replaced. The first shop I visited was on 6/16/25 and that shop stated the spark plugs and coils were fine.
Does this seem like a bad fuel injector only? Or is something likely wrong with the engine? I am worried they are going to jerk me around and say it is only a fuel injector when the issue is much larger, just because they don't want to pay for an engine replacement.
What should I do? I don't know what is right and wrong. There was a recall, but they said it's been fixed and that's that. Please help!
Code P0304:
•A recurring Check Engine Light code indicating a specific cylinder misfire in Cylinder 4.
•The issue has persisted for over 1 year, always returning to the exact same cylinder despite parts being replaced.
•The Check Engine Light intermittently turns off on its own after a few smooth drives.
•Most recent scan at Valvoline detected a PERMANENT P0304 code.
Rapid Oil Loss:
•The engine oil has recently started draining and consuming much faster between services without leaving a visible puddle on the ground.
•My engine oil is halfway between Full and Low, yet it has been less than 2,000 miles since my last oil change.
Engine Ticking:
•A distinct metallic ticking noise coming from the engine that started about a year ago and has progressively worsened. It subsides after the engine warms up.
Metal on Sensor:
•An independent inspection by Christian Brothers Automotive physically discovered a metallic debris coating the magnetic crankshaft sensor which caused it to be damaged.
•Mechanic noted that there was no damage to the flex plate teeth.
Rough Starts:
•Intermittent, violent shaking and rough idling immediately upon starting the vehicle when the engine is COLD.
Acceleration:
•Car will not go past 2,500 RPM.
•Car will intermittently ‘fall back’ in power during acceleration. I can feel it physically when driving.
Constant Idle Vibration:
•A slight, continuous vibration felt through the car whenever the vehicle is turned on and idling.
A/C Shudder:
•When the A/C is turned on and the car is idling at a stoplight or in park, the engine experiences a sudden hiccup that feels like a shudder coming from the front hood.
•The A/C shudder has triggered a severe, uncontrollable shaking and jerking of the entire vehicle on a few occasions.
I took my car to the Kia dealership yesterday and they seem intent that this is all based on a bad fuel injector. They said they won't take into account the metallic debris on the crankshaft sensor because they didn't do the repair. I brought the car in to them back in March for the same recurring issues. They said it was bad spark plugs and 2 bad coils, which I had replaced. The first shop I visited was on 6/16/25 and that shop stated the spark plugs and coils were fine.
Does this seem like a bad fuel injector only? Or is something likely wrong with the engine? I am worried they are going to jerk me around and say it is only a fuel injector when the issue is much larger, just because they don't want to pay for an engine replacement.
What should I do? I don't know what is right and wrong. There was a recall, but they said it's been fixed and that's that. Please help!
Sep 4, 2026 at 11:28 AM
