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P0309ModerateEngine

P0309: Cylinder 9 Misfire Detected

1 vehicles · 1 makes · $5,000-$15,000 repair

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P0309 is an OBD-II diagnostic trouble code meaning “Cylinder 9 Misfire Detected.” Misfires detected specifically in cylinder 9. Applies to V10 and V12 engines. This code appears across 1 vehicle models from 1 manufacturers, with repair costs ranging from $5,000 to $15,000.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
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Common Causes

1Failed ignition coil
2Worn spark plug
3Clogged fuel injector
4Low compression
5Valve train issue

Typical Repair Cost

$5,000 - $15,000

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0309, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

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
Check Price on Amazon
Best Value$90–$120

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)
Check Price on Amazon
Advanced$180–$230

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
Check Price on Amazon
Professional$350–$450

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
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

8 SeriesCritical

V12 Nikasil Cylinder Bore Wear (M70/M73)

1991-1997$5,000-$15,0000 reports

Related Codes (8)

P0300Random/Multiple Cylinder Misfire DetectedP0301Cylinder 1 Misfire DetectedP0302Cylinder 2 Misfire DetectedP0303Cylinder 3 Misfire Detected002FManufacturer-Specific Diagnostic Code16566Mass Air Flow Sensor Signal Too Low (VAG)ECM-940AEngine Control Module Fault (Volvo)P0008Engine Position System Performance - Bank 1

FAQ

What does P0309 mean?

P0309 stands for "Cylinder 9 Misfire Detected." Misfires detected specifically in cylinder 9. Applies to V10 and V12 engines.

What are the most common causes of P0309?

The most common causes of P0309 are: Failed ignition coil, Worn spark plug, Clogged fuel injector, Low compression, Valve train issue. The specific cause varies by vehicle.

How much does it cost to fix P0309?

Repair costs for P0309 range from $5,000 to $15,000, depending on the vehicle and root cause.

Which vehicles are affected by P0309?

Au7o has documented P0309 across 1 vehicle models from 1 manufacturers: BMW.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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