P0302 Mercury Code - Cylinder 2 Misfire Detected
Quick Answer
Misfire is defined as a lack of combustion in a cylinder due to the absence of a spark, incorrect fuel metering, low compression, or any other cause. Common causes include Faulty Spark Plug #2, Clogged or faulty Fuel Injector #2, Faulty Ignition Coil #2. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0302 Mercury indicates Cylinder 2 Misfire Detected.
- Common causes
- Common causes include Faulty Spark Plug #2, Clogged or faulty Fuel Injector #2, Faulty Ignition Coil #2.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P0302 Mercury Description
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.
The Malfunction Indicator Lamp (MIL) blinks once per second when detecting a misfire severe enough to cause catalyst damage. If the MIL is in a steady state due to a misfire, this indicates the threshold for emissions was exceeded and caused the vehicle to fail an inspection and maintenance tailpipe test.
This Diagnostic Trouble Code (DTC) sets when the misfire detection monitor detects an engine misfire in cylinder 2.
What are the Possible Causes of the DTC P0302 Mercury?
- Faulty Spark Plug #2
- Clogged or faulty Fuel Injector #2
- Faulty Ignition Coil #2
- Fuel Injector #2 harness is open or shorted
- Fuel Injector #2 circuit poor electrical connection
- Ignition Coil #2 harness is open or shorted
- Ignition Coil #2 circuit poor electrical connection
- Insufficient cylinder 2 compression
- Incorrect fuel pressure
- Intake air leak
How to Fix the DTC P0302 Mercury?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0302 Mercury code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0302 Mercury Code
No Frequently Asked Questions about P0302 Mercury Code found.
Discuss the causes and fixes for P0302 Mercury OBDII Code
-
i am an ASE Certified Tech, but i have a 2008 merc, sable, gives code po302 which is #2 cylinder misfire, had to pull plentim off so i replaced 1,2,3 coil packs and all plugs.no change, so i replaced #2 injector, still no change, should i go to PCM or crank sensor?
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Unfortunately never had that problem before, the only similar issue I had was with a bad fuel injector wire. The wire protector was still OK, but the wire inside was broken. My suggestion is to check continuity between the PCM and fuel injector and ignition coil.
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