Have a 2003 Taurus, 3.0 engine that has a misfire on #2 cylinder. Replaced all spark plugs, wires, coil, replaced the fuel injectors, crank sensor, cam sensor, still have a misfire on #2 cylinder. It has 200lbs of pressure. I am at a loss at could be causing this. Any other suggestions? Thanks

Possible causes - Faulty spark plug 5
- Clogged or faulty fuel injector 5
- Faulty ignition coil 5
- Fuel injector 5 harness is open or shorted
- Fuel injector 5 circuit poor electrical connection
- Ignition coil 5 harness is open or shorted
- Ignition coil 5 circuit poor electrical connection
- Insufficient cylinder 5 compression
- Incorrect fuel pressure
- Intake air leak

The P0305 code means that the cylinder 5 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 5. If the problem persist more tests needs to be done to diagnose problem, see "Possible Causes



When is the code detected? Engine Cylinder 5 is Misfiring.


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 problem is a sparkplug or wire you must be replaced

P0301 - Cylinder 1 Misfire Detected.

Possible Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak at cylinder

Possible Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

Being you have a heavy gas smell I would look into the injectors. If injector #1 is over producing it can cause a misfire. Test your compression and fuel pressure.

P0301 - Cylinder 1 Misfire Detected.


Possible Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak at cylinder


Possible Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

P0301 - Cylinder 1 Misfire Detected.

Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak

Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

P0303 - Cylinder 3 Misfire Detected.
Follow info from P0301.

P0316 - Misfire Occurred In The First 1,000 Engine Revolutions.

Causes:
- Damaged CKP sensor.
- Ignition System.
- Fuel Injectors
- Running out of fuel
- Fuel Quality
- Base engine
- Damaged Powertrain Control Module

Solutions:
Usually the P0316 is combine with a P03XX codes. The P03XX code indicates in which cylinder the misfire occurred.

A code P0300 may mean that one or more of the following has happened:
* Faulty spark plugs or wires
* Faulty coil (pack)
* Faulty oxygen sensor(s)
* Faulty fuel injector(s)
* Burned exhaust valve
* Faulty catalytic converter(s)
* Stuck/blocked EGR valve / passages
* Faulty camshaft position sensor
* Defective computer

Possible Solutions:
* If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
* If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

Hope helps (remember to rate this).

MISFIRE ON CYLINDER 2 COULD BE LEAKING INTAKE AT CYLINDER 2 OR DIRTY CLOGGED FUEL INJECTOR AT 2 CYLINDER.REPLACE AIR FILTER IF IT LOOKS DIRTY AND CLOGGED UP AND CHECK TRANSMISSION FLUID LEVEL.IF FLUID LOOKS BURNT SMELLY CHANGE FLUID AND FILTER.

Replace the coil for number 3 cylinder.

Sound like an air / vacuum leak to me.
Re-check for an air leak on #2 cylinder inlet manifold.
Use a propane torch (unlit, of course) to flood propane gas around inlet manifold/head flange & gasket area.
If there is any change in idle speed during this test you have a vacuum leak.

Have your intake manifold o rings replaced. it is most likely that it would be a vac. leak. and the engine monitor cannot properly diasgnose this problem and having you replace 1000$ in parts and never find the problem.