I I have a 2001 ford expeditionit feels like a misfire.i just replaced all spark plugs and cleaned maf meter.codes ar PO113PO118and PO102.Thanks.

Clean MAF and Throttle body with the proper cleaner spray. The codes should tell you the issue but if you get it onto a high end scan tool, you can access the live data as well.

code p0102 refers to MAF/VAF sensor ---low input ===causes --wiring short to ground. MAF/VAF sensor
code po172 refers to system too rich --bank 1=== causes ---intake blocked --EVAP canister purge valve---fuel pressure ---HO2S sensor
code po random misfires ---plugs --wiring ---injectors--low compression
code po305 refers to cylinder 5 misfire detected ===causes --engine mechanical fault--ignition/ fuel system ---injector ---ECT/MAF

I would check that the air filter is not blocked first as it affects the MAF/VAF sensors . Have a fuel pressure system pressure test done

the misfire could be the distrubiter cap also could be bad...tha cap is where the other ends of the spark plug wire go

have you cleared the codes between fault reads
clean the maf first .....replace the maf if faulty
coil packs ?
injectors

code p 0306 is misfire detected no 6 cylinder causes electrics
more likely a bad injector , injector wiring or dirty tip

Please go to this page for engine misfire causes.

clean the MAF, Mas Air Flow Sensor in the air intake tube first. Use carb cleaner or MAF cleaner. Do not touch the 2 sensor wires that you spray. delicate!!

ALso, put a bottle of Chevron Techron Fuel injector cleaner in the fuel tank, 1/4 tank or less.

Try that first. Also, replace spark plugs, put antiseize on the threads. Last resort is to replace the COPS, Coil on plug for each offending cylinder.

Misfire Definition: A misfiring cylinder is lacking power relative to the other cylinders. The causes for a cylinder specific misfire could be fuel, spark, or mechanical problems. Perform a thorough visual inspection. If no visible concerns are found use the following WDS tools for misfire diagnosis:

• Self-test (Check for codes first)
• Power Balance (Identify the cylinder of concern)
• Relative Compression (Rule out a possible mechanical issue)
• Fuel (Make sure fuel injectors are not restricted) (plugged)
• Ignition (Make sure spark plugs and coils are working properly)
• Oscilloscope (Detailed signal analysis)

There is no spark plug relay

You may have had a COP Ignition Coil,changed for #2, based on a PO302 code

What codes do you have now?

Sometimes the code won't tell you which coil is bad,if it is a bad spike,it will set a lot of wrong codes.

The PO300 Misfire, first 1000 Revolutions,you forget, means nothing to you.

You may have to buy a new coil and move it from one cylinder to the next,to find the bad one.

Unfortunately you have to remove the intake manifold, to do right bank coils

Hope your not still on 5 year old spark plugs. If so, remove intake,do plugs,install 3 new coils, on back cylinders and save them, to use on future coil issues or front bank,current problems.

Clean MAF Sensor (CRC MAF Cleaner)
Clean throttle plate (CRC Throttle Body Cleaner)
Meter out TPS Sensor----check for wear/inconsistant PCM feed back

check that your spark plugs are new and gaped to specs.
Check your coil for any signs of wear sometimes they can receive hairline fractures and cause misfire. And check your MAF sensor this can cause misfire this is the sensor inline after your air filter. Pull it out and clean it preferably with some light solvent or WD-40 will do.

here's the scoop. There is a TSB that addresses this issue.
First, replace the spark plugs.
Next, replace all 6 COPS, coil on plug. You have to because they feed back into the PCM, Powertrain Control Module and blow the drivers. Then you need to replace the PCM.

This was for 2004-06, but it might apply to yours if it's a 3.0L.
buy at tascafordparts.com.

Misfire DTC codes identify which cylinder is misfiring.

Misfire Detection Monitor The Misfire Detection Monitor is an on-board strategy designed to monitor engine misfire and identify the specific cylinder in which the misfire has occurred. Misfire is defined as lack of combustion in a cylinder due to absence of spark, poor fuel metering, poor compression, or any other cause. The Misfire Detection Monitor will be enabled only when certain base engine conditions are first satisfied. Input from the ECT or CHT, MAF and CKP sensors is required to enable the monitor. The Misfire Detection Monitor is also performed during on demand self-test.

1. The PCM synchronized ignition spark is based on information received from the CKP sensor. The CKP signal generated is also the main input used in determining cylinder misfire.

1. The input signal generated by the CKP sensor is derived by sensing the passage of teeth from the crankshaft position wheel mounted on the end of the crankshaft.

1. The input signal to the PCM is then used to calculate the time between CKP edges and also crankshaft rotational velocity and acceleration. By comparing the accelerations of each cylinder event, the power loss of each cylinder is determined. When the power loss of a particular cylinder is sufficiently less than a calibrated value and other criteria is met, then the suspect cylinder is determined to have misfired.

1. Misfire type A:
   
   Upon detection of a Misfire type A (200 revolutions) which would cause catalyst damage, the MIL will blink once per second during the actual misfire, and a DTC will be stored.
   
   Misfire type B:
   
   Upon detection of a Misfire type B (1000 revolutions) which will exceed the emissions threshold or cause a vehicle to fail an inspection and maintenance tailpipe emissions test, the MIL will illuminate and a DTC will be stored.
   
   The DTC associated with multiple cylinder misfire for a Type A or Type B misfire is DTC P0300.
   
   The DTCs associated with an individual cylinder misfire for a Type A or Type B misfire are DTCs P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309 and P0310.