P0308 on 2011-2023 Dodge Durango 5.7L HEMI: Cylinder 8 Misfire Causes and Fixes

What's Unique About the 2011-2023 Dodge Durango

While any V8 can log a P0308, on the 5.7L HEMI in the Durango, this code must be taken seriously due to the engine's well-documented history of camshaft and lifter failures. The Multi-Displacement System (MDS) uses specialized lifters that are a known weak point. A failure often starts as a single-cylinder misfire and a distinct ticking sound. One forum user with a P0308 and ticking on their Ram 1500 confirmed the cause was worn camshaft lobes from failed lifters. Another user reported a $6,900 repair bill for a new camshaft and lifters to resolve a P0308 code. It's often not the MDS lifters themselves that fail; cylinders 7 and 8 are at the end of the oiling galley, and inadequate lubrication can cause even non-MDS lifters to seize and destroy the cam lobe.

Symptoms You May Notice

• Rough or shaking idle.
• Hesitation or stumbling during acceleration.
• Noticeable loss of engine power.
• Flashing or solid Check Engine Light.
• A rhythmic ticking or tapping noise from the engine, often called the 'HEMI tick', especially from the passenger side wheel well.
• Reduced fuel economy.
• Smell of fuel from the exhaust.

Most Likely Causes

1. Worn or Faulty Spark Plugs 🔴 High Probability The 5.7L HEMI uses two spark plugs per cylinder (16 total), increasing the chances of a single plug failing. They are a regular maintenance item with a recommended change interval.
   How to confirm: Inspect the two spark plugs for cylinder 8. Look for heavy carbon buildup, oil fouling, or a worn-out electrode. A simple fix is to replace them, as they are a routine maintenance item.
   Typical fix: Replace the spark plugs for cylinder 8. It is best practice to replace all 16 spark plugs 🎬 Watch: Step-by-step guide to replacing HEMI spark plugs and coils. at the same time to ensure consistent performance.
   Est. part cost: $50-$150 for a set of 16 high-quality plugs from brands like NGK or Champion.
2. Faulty Ignition Coil 🔴 High Probability
   How to confirm: Swap the ignition coil from cylinder 8 with another cylinder (e.g., cylinder 6). Clear the codes and drive the vehicle. If the code changes to P0306, the ignition coil is the culprit. This is a standard and effective diagnostic step mentioned in numerous forums.
   Typical fix: Replace the faulty ignition coil. It is a simple, single-bolt replacement.
   Est. part cost: $40-$90 for one OEM Mopar coil (Part #5149168AI or its successor 5149168AJ).
3. Failed MDS Lifter and/or Damaged Camshaft 🟡 Medium Probability This is a widely documented failure point on the 5.7L HEMI. Lack of lubrication (especially to rear cylinders like #8), long oil change intervals, and the design of the lifters can lead to the lifter's roller bearing failing, which then grinds down the camshaft lobe. Technicians on forums report seeing this repair on a monthly basis.
   How to confirm: This is often accompanied by a persistent ticking noise. A compression test or cylinder leak-down test may show poor results for cylinder 8. A definitive, though labor-intensive, method is to remove the valve cover and watch the rocker arms on cylinder 8 while the engine is manually turned over; reduced movement indicates a wiped cam lobe. The ultimate confirmation requires physically inspecting the camshaft and lifters.
   Typical fix: This is a major and expensive repair that involves replacing the camshaft, all 16 lifters (often with an upgraded non-MDS design), head gaskets, and other related components. Many owners opt for a non-MDS conversion kit 🎬 See how to perform a full camshaft and lifter replacement. for improved reliability. This is not a simple DIY job.
   Est. part cost: $800-$2000+ for a full cam and lifter kit. A forum member reported a shop quote of $3k-5k for the full job.
4. Clogged or Faulty Fuel Injector ⚪ Low Probability
   How to confirm: After ruling out spark and coil, the fuel injector is the next suspect. You can swap the injector from cylinder 8 with another cylinder, similar to the coil test. If the misfire code follows the injector, it needs to be replaced. You can also test the injector's circuit with a noid light.
   Typical fix: Replace the faulty fuel injector. It's often recommended to replace them as a set on high-mileage vehicles.
   Est. part cost: $70-$150 for one OEM-quality injector (Part numbers like 5281568AA or 53032713AB may apply depending on the year).

Rare But Worth Checking

• PCM Software Issue: A Technical Service Bulletin (TSB 18-006-24) for the similar Ram 1500 with the same engine notes that overly sensitive misfire detection logic can sometimes set false codes. A dealer can check if a software update is available for your vehicle's PCM.
• Vacuum Leak: A leak in the intake manifold gasket near the cylinder 8 runner could lean out the mixture enough to cause a misfire. This is less common for a single-cylinder misfire but can be checked with a smoke test.
• Wiring Harness Issue: A user on a Ram forum discovered a rodent had chewed into an injector wire, causing a persistent misfire on one cylinder. Inspecting the wiring harness to the coil and injector for damage is a valid diagnostic step.

Diagnosis Steps

1. Confirm the code with an OBD-II scanner. Note if the check engine light is solid or flashing.
2. Listen for a rhythmic ticking noise from the engine bay, especially at idle near the passenger-side wheel well. A tick is a strong clue for lifter/camshaft issues.
3. Swap the ignition coil from cylinder 8 (passenger side, rear) with the coil from cylinder 6 (passenger side, third from front). Clear the codes. If the misfire moves to P0306, the coil is bad.
🎬 Watch: A quick breakdown of diagnosing a Cylinder 8 misfire.
4. If the misfire remains on cylinder 8, inspect and replace the two spark plugs for that cylinder. They are a common wear item.
5. If the misfire persists, inspect the wiring harness for the coil and fuel injector for any visible damage, such as from chafing or rodents.
6. (Advanced) Swap the fuel injector from cylinder 8 with another cylinder. If the misfire moves, the injector is bad.
7. (Advanced) If all else fails, perform a compression test and a cylinder leak-down test on cylinder 8. Low compression points towards internal mechanical damage, such as a worn camshaft lobe from a failed lifter.
8. (Professional) If a wiped cam lobe is suspected, a technician can remove the valve cover to visually inspect valve movement while turning the crankshaft by hand.

Parts You'll Likely Need

• Ignition Coil (OEM #5149168AI (superseded by 5149168AJ)) — Ignition coils are a very common failure point causing single-cylinder misfires. It's one of the first parts to test via swapping.
  Trusted brands: Mopar, NGK, Denso
  OEM price range: $60-$90
  Aftermarket price range: $40-$70
• Spark Plugs (Iridium or Nickel) (OEM #SPLZFR5C11 or SP143877AB (varies by year)) — The HEMI engine uses 16 spark plugs that are a scheduled maintenance item. A worn or fouled plug is a primary cause of misfires.
  Trusted brands: NGK, Champion, Autolite
  OEM price range: $10-$20 per plug
  Aftermarket price range: $7-$15 per plug
• Camshaft and Lifter Kit (OEM #Lifters: 5038784AD (Non-MDS)) — This is the definitive fix for the 'HEMI tick' and a misfire caused by a failed lifter. The kit should include a new camshaft, new lifters (often non-MDS for improved reliability), and necessary gaskets.
  Trusted brands: Mopar, Modern Muscle Xtreme (MMX), Comp Cams, Melling
  OEM price range: $1200-$2000
  Aftermarket price range: $800-$1500

Related Codes That Often Appear With This One

• P0300 — If the misfire is severe or intermittent across multiple cylinders, a P0300 (Random Misfire Detected) may be stored alongside P0308. This is common in the early stages of lifter failure before the damage is isolated to one cylinder.
• P2323 — A code for 'Ignition Coil H Secondary Circuit' (where H is the 8th letter) can sometimes accompany P0308, pointing more directly to a failure in the ignition coil's high-voltage output.

Technical Service Bulletins (TSBs) & Recalls

• TSB #18-006-24 (for Ram 1500, but relevant): Notes that a PCM software update may correct overly sensitive misfire detection for codes like P0300-P0308.
• TSB Bulletin #1400322REVA: Notes that customers may describe a rough idle or misfire while driving associated with codes P0303 through P0308.
• TSB Bulletin #18-093-15: Describes a condition where a rough idle and misfire codes P0300 through P0308 can occur when the vehicle is started cold and immediately placed in gear.

Platform-Specific Known Issues

• The 5.7L HEMI V8 from 2009 onwards is known for a design issue related to the valvetrain, particularly the lifters. Insufficient lubrication at idle, extended oil change intervals, and the design of the lifter's needle bearings can lead to premature failure. This failure causes the lifter to stop rolling and start dragging on the camshaft lobe, quickly destroying both components and sending metal particles through the engine. This often begins as a single-cylinder misfire code like P0308 and a ticking sound. Cylinders 7 and 8 are particularly vulnerable as they are at the end of the oiling passage.

Mechanic-Grade Diagnostic Values

• Ignition Coil Primary Resistance — expected: 0.4 to 2.0 ohms. Failure: A reading outside this range, or an open circuit (OL), indicates a faulty coil.
• Ignition Coil Secondary Resistance — expected: 6,000 to 10,000 ohms (6k-10k Ω). Failure: Readings significantly higher or lower suggest the coil's secondary winding has failed.
• Ignition Coil Connector Voltage (Key On, Engine Off) — expected: ~12V (Battery Voltage). Failure: No voltage indicates a problem with the ASD (Auto Shutdown) relay or wiring from the PDC. Voltage is only present for a few seconds after turning the key to 'ON' before the PCM cuts it.
• Fuel Pressure (Key On, Engine Off) — expected: 58 ± 5 PSI. Failure: Low pressure can cause lean misfires across multiple cylinders, but a failing regulator could potentially affect a single cylinder at the end of the fuel rail. High pressure is also indicative of a regulator problem.

Scan Tool Commands That Help

• wiTECH or advanced bidirectional scanner: Cylinder Power Balance Test — This test is invaluable when the cause of the misfire isn't a simple spark or coil issue. The tool deactivates each cylinder one by one and measures the RPM drop. If disabling cylinder 8 causes little or no drop in RPM compared to other cylinders, it confirms cylinder 8 is not contributing power, pointing to a fuel, spark, or compression issue specific to that cylinder.
• wiTECH or advanced bidirectional scanner: Fuel Injector Kill — Similar to the power balance test, this allows a technician to manually disable the fuel injector for cylinder 8. If the engine's running condition does not change when the injector is killed, it suggests the injector was not working in the first place, or that there is a more significant mechanical or ignition problem preventing combustion.

Wiring & Ground Locations

• G904 / G905 — Lower left (driver's) side of the engine block.. These are primary engine ground points. A loose or corroded ground here can cause a host of erratic electrical issues, including weak spark or faulty sensor readings that could lead to a misfire code.
• Cylinder 8 Ignition Coil Connector — Passenger side of the engine, rearmost coil. The power feed wire is typically Dark Green/Orange (DG/OR).. This is the direct connection for testing voltage supply to the coil. Technicians will back-probe this connector to verify the ~12V from the ASD relay is present when the key is turned on.
• Passenger Side D-Pillar Ground — Located behind the trim in the D-pillar on the passenger side, near the cargo area.. While not a primary engine ground, various body control modules and sensors ground here. In rare cases, electrical feedback or noise from a poor ground in this area can affect sensitive PCM calculations, although it's an unlikely cause for a single cylinder misfire.

Real Owner Repair Stories

• RamForumz user (2012 Ram 1500 5.7L HEMI) — P0308 misfire, rough idle, ticking noise.
  ❌ Tried (didn't work) Replaced spark plugs, Swapped ignition coils
  ✅ What actually fixed it The final diagnosis was a failed lifter and a wiped camshaft lobe for cylinder #8. The owner opted for a full camshaft and lifter replacement, which resolved the misfire and the ticking noise.
• DodgeTalk Forum user (2011 Ram 1500 5.7L HEMI with 130,000 miles) — P0308, flashing check engine light, significant ticking sound.
  ❌ Tried (didn't work) Initial diagnosis focused on spark plugs and coils.
  ✅ What actually fixed it A broken valve spring on cylinder #8 was discovered. The spring had failed, causing the valve to not seat properly, leading to a complete loss of compression on that cylinder. Replacing the valve spring and related seals fixed the issue.
• NHTSA ODI #10297723 — An owner reported the engine chugs, has a rough idle, and no power to merge with traffic. After finding codes P0308 and P2099, they discovered several spark plugs showed signs of sitting in water.
• NHTSA ODI #10357753 — An owner noted the engine started missing and showed code P0308. Despite checking the spark plug, coil, wiring, and injector and finding them all okay, the engine continued to have issues.

OEM Part Supersession History

• 5149168AI → 5149168AJ — Standard part revision and improvement by the manufacturer.
  Heads up: The part numbers are generally interchangeable, but 5149168AJ is the current recommended replacement for vehicles manufactured after July 13, 2010.

Model Year Variations Within This Range

• 2009-Present: In 2009, the 5.7L HEMI was updated with Variable Camshaft Timing (VCT), also known as variable valve timing (VVT). This added a phaser to the camshaft and a control solenoid. While this doesn't change the fundamental diagnosis for a P0308, a malfunctioning VCT system could theoretically cause timing-related misfires, though it would typically affect an entire cylinder bank (e.g., P0302, P0304, P0306, P0308) rather than just a single cylinder.

Diagnostic Flowchart

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0300 — Random/Multiple Cylinder Misfire Detected. Mentioned in TSB #18-006-24 alongside P0308 regarding overly sensitive misfire detection requiring a PCM software update.
• P0306 — Cylinder 6 Misfire Detected. Often seen during diagnostics when swapping the ignition coil from cylinder 8 to cylinder 6 to verify a faulty coil.
• P2323 — Ignition Coil 8 Secondary Circuit. Reported by owners alongside P0308 when experiencing severe mechanical failures like a wiped camshaft and failed lifter.
• P0307 — Cylinder 7 Misfire Detected. Cylinder 7 shares the same vulnerability as cylinder 8, as both are at the end of the 5.7L HEMI oiling passage and are highly susceptible to lifter failure.

Frequently Asked Questions