2019 Dodge Charger 6.4 HEMI Tick Noise & Misfire (P0304) – Full Diagnostic Breakdown
Introduction
If you’ve ever started up your car and heard a sharp ticking noise that just didn’t sound right, you know that sinking feeling. Now add a check engine light on top of that, and you’ve got a situation that needs attention—fast.
In this case, we’re working with a 2019 Dodge Charger equipped with the 6.4L 392 HEMI, a powerful engine known for performance—but also known in the field for a few very specific failure patterns.
The symptoms were clear: a heavy valvetrain ticking noise and a check engine light. These are not the kind of symptoms you ignore. When you’re diagnosing car problems like this, understanding what those sounds and codes are telling you can save an engine—or cost you one if overlooked.
Let’s walk through this step by step.
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Vehicle Overview
This vehicle is a 2019 Dodge Charger with the 6.4L (392) HEMI engine. It features cylinder deactivation (MDS – Multi-Displacement System), which improves fuel economy but also introduces additional valvetrain components—specifically MDS lifters.
From a diagnostic standpoint, that detail matters.
Vehicle Concern
The vehicle was driven into the shop with two primary symptoms:
Check engine light illuminated
Noticeable ticking noise from the engine
The ticking was described as valvetrain-related, not a deep knock. That distinction is critical when diagnosing car problems because it helps narrow down whether you’re dealing with top-end or bottom-end issues.
Initial Inspection
Right away, the noise stood out. It had that sharp, rhythmic tick that increases with RPM—classic valvetrain behavior.
No obvious external issues were found. Oil level wasn’t flagged as a concern, and there were no immediate signs of external damage or leaks that would explain the noise.
At this point, the next step in any solid automotive troubleshooting process is simple: scan the vehicle and see what the data says.
Codes
The scan revealed:
P0304 – Cylinder 4 Misfire (stored in PCM)
P1009 – Humidity sensor (BCM)
The P1009 code is unrelated to the drivability issue and can be set aside for now.
The real focus is P0304, which tells us cylinder 4 is misfiring.
Diagnostic Process
Here’s where experience comes into play.
A less experienced tech might immediately start swapping coils, plugs, or injectors. But when you combine a specific cylinder misfire with a mechanical ticking noise, you have to think deeper.
Ignition and fuel problems don’t create mechanical noise.
So instead of chasing components, the focus shifts to mechanical integrity.
On a 6.4 HEMI, especially one equipped with MDS, there’s a well-known pattern:
Lifter failure
Camshaft lobe wear
Resulting misfire
Cylinder 4 is one of the cylinders affected by the MDS system, which uses specialized lifters that can collapse under certain conditions. When those lifters fail, they stop following the camshaft properly.
That leads to reduced or no valve lift—meaning the cylinder can’t breathe correctly—and that results in a misfire.
At the same time, the failed lifter creates excessive clearance, which produces that ticking noise.
This is why pattern recognition is so important in automotive troubleshooting. You’re not just reading codes—you’re interpreting symptoms.
Key Findings
Everything lined up:
Single-cylinder misfire (cylinder 4)
Consistent valvetrain ticking noise
Engine equipped with MDS lifters
There was no evidence pointing toward ignition or fuel as the root cause. The noise alone ruled that out.
At this point, further disassembly would only serve to visually confirm what experience already made clear.
Final Diagnosis
The engine has an internal valvetrain failure, most likely:
Collapsed MDS lifter on cylinder 4
Associated camshaft lobe wear
This condition causes both the ticking noise and the misfire. Continued operation will only make the damage worse, potentially leading to metal contamination throughout the engine.
The correct repair is:
Camshaft replacement
Full lifter replacement (not just one)
Associated gaskets, bolts, and timing components
Common Causes
This type of failure isn’t random. There are a few common causes seen repeatedly in the field:
Poor lubrication or oil quality can accelerate lifter wear. These engines rely heavily on clean, consistent oil flow to keep lifters functioning properly.
MDS system design itself is another factor. The added complexity introduces more potential failure points compared to traditional lifter setups.
Extended oil change intervals also play a role. Skipping maintenance or stretching intervals too far can lead to internal wear that eventually shows up as noise and misfires.
And finally, normal wear over time—especially in performance engines like the 392 HEMI—can lead to component fatigue.
Lessons for Buyers / DIYers
This case is a perfect example of why understanding symptoms matters.
If you’re hearing a ticking noise, don’t ignore it. That sound is often your first warning sign of a much bigger problem.
When diagnosing car problems, always look at the full picture:
What does it sound like?
What codes are present?
How do those symptoms connect?
For anyone looking at used car inspection tips, this is critical. A quick test drive might not reveal a failing lifter, but a trained ear and a proper scan can.
Also, don’t fall into the trap of throwing parts at a problem. Automotive troubleshooting is about strategy, not guessing. Understanding common causes and patterns will save you time and money.
Don’t Get Burned on Your Next Used Car
If you’re thinking about buying a used car—or even if you already have one—this is exactly the kind of problem that can slip through the cracks and cost you big money later.
After 35+ years in the automotive field, I’ve seen firsthand how often people end up with vehicles that have hidden issues just like this.
That’s why I put together a simple Used Car Guide to help you understand what to look for and how to avoid making a costly mistake.
It’s a quick, practical guide designed to give you the right mindset and approach before you buy.
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AFFILIATE DISCLAIMER
Disclaimer: Some links in this post may be affiliate links. I may earn a small commission at no extra cost to you. I only recommend tools I personally use and trust in real-world diagnostics.
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