P0308: Cylinder 8 Misfire Detected
24 vehicles · 12 makes · $100-$12,000 repair
Most Reported On
P0308 is an OBD-II diagnostic trouble code meaning “Cylinder 8 Misfire Detected.” P0308 means the engine computer detected a misfire on cylinder number 8 — that cylinder is failing to combust properly or at the correct time. The PCM identifies it by monitoring crankshaft speed variations as cylinder 8 fires. Misfires waste fuel, increase emissions, and can overheat and damage the catalytic converter, so a hard misfire may cause a flashing check engine light. Typical symptoms include rough idle, vibration, hesitation, and reduced power. This code is most commonly reported on 2011-2023 Chrysler 300 (300C, C, S, SRT8), 2009-2019 RAM 1500, and 2011-2023 Dodge Durango (Citadel, Limited, R/T, SRT, SRT 392, SRT Hellcat), plus 21 other vehicles, with repair costs ranging from $100 to $12,000.
Common Causes
Typical Repair Cost
Based on 29 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0308, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (24)
HEMI MDS Lifter Tick
HEMI MDS Lifter Tick
Pentastar V6 Rocker Arm/Lifter Tick
HEMI Lifter/MDS Tick
Pentastar V6 Rocker Arm/Lifter Tick
Random Misfire / Rough Idle (P0300) From Worn Spark Plugs & Failing Ignition Coils
Intake Plenum Pan Gasket Failure (Magnum V6/V8) Causing Oil Consumption and Misfire
Valve Spring Failure on 6.4L 392 HEMI (High-RPM and Modified/Boosted Cars)
Triton 2-Valve Spark Plug Blow-Out from Cylinder Head
4.6L 2-Valve Triton V8 Spark Plug Ejection / Stripped Head Threads (TSB 07-21-2)
5.4L 2-Valve Spark Plug Blow-Out From Cylinder Head
4.6L 2-Valve Spark Plug Ejection/Breakage
HEMI Lifter/Camshaft Failure
MDS Lifter Failure and Hemi Tick (5.7L)
6.4L HEMI Valvetrain Failure (Roller Lifter/Camshaft Wear, "HEMI Tick")
5.7L HEMI MDS Lifter Failure
FAQ
What does P0308 mean?
P0308 stands for "Cylinder 8 Misfire Detected." P0308 means the engine computer detected a misfire on cylinder number 8 — that cylinder is failing to combust properly or at the correct time. The PCM identifies it by monitoring crankshaft speed variations as cylinder 8 fires. Misfires waste fuel, increase emissions, and can overheat and damage the catalytic converter, so a hard misfire may cause a flashing check engine light. Typical symptoms include rough idle, vibration, hesitation, and reduced power.
What are the most common causes of P0308?
The most common causes of P0308 are: Worn, fouled, or incorrectly gapped spark plug on cylinder 8, Failed ignition coil or coil-on-plug for cylinder 8, Faulty, clogged, or leaking fuel injector, Vacuum or intake air leak affecting that cylinder, Low compression (worn rings, burnt/leaking valve, head gasket), Damaged spark plug wire or boot (on applicable engines), Carbon buildup or sticking valve. The specific cause varies by vehicle.
How much does it cost to fix P0308?
Repair costs for P0308 range from $100 to $12,000, depending on the vehicle and root cause.
Which vehicles are affected by P0308?
Au7o has documented P0308 across 24 vehicle models from 12 manufacturers: Audi, Chevrolet, Chrysler, Dodge, Ford, GMC, Jaguar, Jeep, Lincoln, RAM, Ram, Volkswagen.
Sources (12)
- ForumRamForumz: Cam / lifter failure class action
- ForumRamForumz: Ram hemi cam/lifter failure thread
- otherCarComplaints: 2011 Dodge Ram 1500 Lifter And Cam Issue
- ForumRamForumz: Cam / lifter failure class action page 4
- ForumRamForumz: Ram hemi cam/lifter failure thread page 8
- videoYouTube - How to Fix HEMI MDS Lifter Tick on Jeep Grand Cherokee by Scotty Kilmer
- mediaWhy Do Ford Triton Engines Blow Out Spark Plugs - Matson Point S
- mediaFord Spark Plug Blow Out Solved - Wise Auto Tools
- mediaFord 5.4 Triton Spark Plug Blew Out Solution - SoutheastCylinderHead
- articleDodge Challenger Spark Plug Replacement Cost Estimate — RepairPal
- articleDodge Challenger Ignition Coil Replacement Cost Estimate — RepairPal
- articleP0300 on 2011-2018 Dodge Challenger: Random Misfire Causes and Fixes — Go-Parts
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.