P0303 1999 Ford F150 Code - Cylinder 3 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 #3, Clogged or faulty Fuel Injector #3, Faulty Ignition Coil #3. 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
- P0303 1999 Ford F150 indicates Cylinder 3 Misfire Detected.
- Common causes
- Common causes include Faulty Spark Plug #3, Clogged or faulty Fuel Injector #3, Faulty Ignition Coil #3.
- 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 P0303 1999 Ford F150 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 3.
What are the Possible Causes of the DTC P0303 1999 Ford F150?
- Faulty Spark Plug #3
- Clogged or faulty Fuel Injector #3
- Faulty Ignition Coil #3
- Fuel Injector #3 harness is open or shorted
- Fuel Injector #3 circuit poor electrical connection
- Ignition Coil #3 harness is open or shorted
- Ignition Coil #3 circuit poor electrical connection
- Insufficient cylinder 3 compression
- Incorrect fuel pressure
- Intake air leak
- EVAP canister purge valve
- Evaporative emission system
How to Fix the DTC P0303 1999 Ford F150?
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 P0303 1999 Ford F150 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 P0303 1999 Ford F150 Code
1. What are the common symptoms of OBDII code P0303 in a 1999 Ford F150?
A: Common symptoms of cylinder 3 misfire detected (P0303) include engine rough idling, loss of power, hesitation during acceleration, and potential engine shaking.
2. What are the possible causes of the P0303 code in a 1999 Ford F150?
A: The P0303 code in a 1999 Ford F150 is commonly caused by issues such as a faulty spark plug, ignition coil, fuel injector, vacuum leak, or low compression in cylinder 3.
3. How can I diagnose the cylinder 3 misfire on my 1999 Ford F150?
A: To diagnose a cylinder 3 misfire, you can perform a visual inspection of spark plugs, check ignition coils, test fuel injectors, inspect for vacuum leaks, and conduct a compression test on cylinder 3.
4. Can driving with a P0303 code in my 1999 Ford F150 cause further damage?
A: Driving with a cylinder 3 misfire detected code can potentially cause damage to the catalytic converter over time due to unburned fuel entering the exhaust system.
5. How can I repair the P0303 code in my 1999 Ford F150?
A: Repairing the P0303 code involves addressing the specific cause of the misfire, such as replacing a faulty spark plug, ignition coil, fuel injector, or repairing vacuum leaks in cylinder 3.
6. Is it safe to continue driving my 1999 Ford F150 with a P0303 code?
A: It is not recommended to drive the vehicle with a P0303 code for an extended period as it can lead to reduced fuel efficiency, engine performance, and potential damage to the catalytic converter.
7. Can a dirty fuel injector cause the P0303 code in a 1999 Ford F150?
A: Yes, a dirty or clogged fuel injector in cylinder 3 can cause a misfire and trigger the P0303 code in a 1999 Ford F150.
8. How much does it typically cost to repair a cylinder 3 misfire in a 1999 Ford F150?
A: The cost of repairing a cylinder 3 misfire in a 1999 Ford F150 can vary depending on the specific cause, but it may range from $100 to $500 or more, including parts and labor.
9. Will resetting the OBDII code P0303 in my 1999 Ford F150 make the issue go away?
A: Resetting the OBDII code P0303 may temporarily clear the check engine light, but it will not fix the underlying issue causing the cylinder 3 misfire in your 1999 Ford F150.
10. Can a bad ignition coil cause only one cylinder to misfire in a 1999 Ford F150?
A: Yes, a faulty ignition coil can cause a misfire in a specific cylinder, such as cylinder 3, leading to the OBDII code P0303 in a 1999 Ford F150.
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