P0311
Cylinder 11 Misfire Detected
When a vehicle powertrain module registers the fault code P0311, it points directly to an internal system malfunction identified as "Cylinder 11 Misfire Detected". Operating your engine under this condition may degrade long-term fuel maps.
Driver's Summary
Your vehicle's computer logged P0311 after detecting a malfunction in the cylinder 11 misfire detected system. You may notice v12 engine running rough, raw fuel smell, flashing mil, all of which are direct consequences of this malfunction. This is not a code to ignore — the underlying fault can rapidly worsen and lead to costly repairs if driving continues.
Symptoms
V12 engine running rough, raw fuel smell, flashing MIL
Common Causes
- Defective spark plug
- Failed ignition coil
- Burnt exhaust valve
- Wiring harness issue
How to Fix
- 1 Replace spark plug
- 2 Replace ignition coil
- 3 Perform leak-down test
- 4 Repair ignition wiring
Technical Explanation
To set P0311, the PCM samples the affected circuit multiple times per second, comparing live readings against manufacturer-programmed operating windows. Misfire rate is counted per cylinder over rolling windows and compared against two thresholds: a catalyst-damaging rate (triggers flashing MIL) and an emissions-exceeding rate (triggers solid MIL). The PCM logs which cylinder is misfiring based on crankshaft position at the time of each detected event. After two failed drive cycles, the code transitions from a pending to a confirmed DTC, and the PCM activates the MIL. Clearing the code without repairing the fault will result in re-illumination within one to two complete drive cycles.
Is It Safe to Drive?
With P0311 active, your engine or transmission is not operating within design parameters. Short-term driving may seem fine, but internal damage is accumulating — particularly to defective spark plug.
Mechanic's Pro Tip
For P0311, test the solenoid's coil resistance with a multimeter before ordering parts — most solenoids should read between 14 and 40 ohms; an open (infinite resistance) or short (near zero) confirms it's failed electrically. Also verify the PCM is commanding the solenoid by backprobing the connector with a test light during the relevant operating condition — if there's no command signal, the fault is in the PCM or wiring, not the solenoid itself.
Related Fault Codes
Frequently Asked Questions
What does OBD2 code P0311 mean?
OBD2 code P0311 refers to Cylinder 11 Misfire Detected. When a vehicle powertrain module registers the fault code P0311, it points directly to an internal system malfunction identified as "Cylinder 11 Misfire Detected". Operating your engine under this condition may degrade long-term fuel maps.
What are the most common symptoms of DTC P0311?
Drivers experiencing code P0311 typically report: V12 engine running rough, raw fuel smell, flashing MIL.
Is it safe to drive with trouble code P0311 active?
With P0311 active, your engine or transmission is not operating within design parameters. Short-term driving may seem fine, but internal damage is accumulating — particularly to defective spark plug.
How much does it cost to fix code P0311?
The estimated repair cost for P0311 ranges from $150 to $2000 USD. Ignition parts: 150 - 400; Valve job: 1,500+
Ignition parts: 150 - 400; Valve job: 1,500+
Need Professional Diagnostic Assistance?
Always verify sensor signals and wiring integrity with an OBD2 scanner before purchasing replacement parts.
Explore All Powertrain Codes →