P0174 - System to Lean (Bank 2) The Adaptive Fuel Strategy continuously monitors the fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. Refer to
Section 1 , Powertrain Control Software, Fuel Trim for more information. See Possible Causes for DTC P0171.
P0171 - System to Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. Refer to
Section 1 , Powertrain Control Software, Fuel Trim for more information. Air Measurement System
- MAF sensor (contaminated, damaged, malfunctioning, etc.)
Fuel System
- Fuel pressure regulator (leaking, malfunctioning, etc.).
- Fuel filter plugged, dirty.
- Fuel pump (weak, check valve leaking, etc.).
- Leaking/contaminated fuel injectors.
- Low fuel pressure or running out of fuel.
- EVAP canister purge valve leaking (when canister is "clean").
- Fuel supply line restricted.
- Fuel rail pressure sensor (incorrect reading).
Air Induction System
- Air leaks after the MAF.
- Vacuum Leaks.
- PCV system (leak, valve stuck open, etc.)
- Improperly seated engine oil dipstick.
Exhaust System
- Exhaust leaks before or near the HO2Ss (exhaust manifold gasket, mating gaskets, etc.)..
EGR System
- EGR valve tube/gasket leak
- EVR solenoid vacuum leak
Secondary Air Injection
- Damaged/malfunctioning secondary air injection system (mechanically stuck valve).
P0300 - Random Misfire The random misfire DTC indicates multiple cylinders are misfiring or the PCM cannot identify which cylinder is misfiring.
- Camshaft position sensor (CMP)
- Low fuel: less than 1/8 tank
- Stuck open EGR valve
- Blocked EGR passages
One or more EGR passages may be blocked or partially blocked. If this is the case the Misfire Detection Monitor will indicate the EGR port to check for possible blockage.
P0301 through P0310 - Misfire Detection Monitor The misfire detection monitor is 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.
- Ignition system
- Fuel injectors
- Running out of fuel
- EVAP canister purge valve
- Fuel pressure
- Evaporative emission system
- Base engine
The MIL will blink once per second when a misfire is detected severe enough to cause catalyst damage. If the MIL is on steady state, due to a misfire, this will indicate the threshold for emissions was exceeded and cause the vehicle to fail an inspection and maintenance tailpipe test.
P0316 - Misfire Occurred in the First 1000 Engine Revolutions P0316 code will be set in addition to any type B misfire DTC which occurs in the first 1000 revolution test interval, following engine start.
- Damaged CKP sensor
- Ignition system
- Fuel Injectors
- Running out of fuel
- Fuel Quality
- Base Engine
- Damaged PCM
Freeze Frame Data and the P03XX DTC will also be stored, indicating in which cylinder the misfire occurred.
Read the attached link
http://troubleshootmyvehicle.com/ford/4.6L-5.4L/troubleshooting-p0171-and-p0174-page-1
