I have a 2000 ford explorer spot 2 door and I can't get the check engine light to stay off so I can smog it to renew registration. The codes I am getting are lean bank 1 and 2. It has the 4.0 sohc 4x4 now I have replaced all the injectors the spark plugs the coil pack the wires I pulled the intake off the heads and replaced the o rings replaced all the vacume lines the o2 sensors the fule filter and even had a smoke test done and replaced the air mass flow sensor. Nothen I have done allows me to get rid of the codes I clear the codes and then need to drive it long enough to reset the monitors so I can get it smogged. I don't get more then 20 miles and the check engine light comes back on the same 2codes lean bank 1 and 2. Has anyone else expearenced this and if so what did you do to sole it so the check engine light stays off and the monitors come on . Here in nv I can have only one monitor off to smog but the check engine light can't be on to get it smoged and I have till Sept 8th to get r registration renewed. I need help to figure this out TY MAL11963

 

Recheck for vacuum leak. Crack in the manifold? Other gasket not so good?

Have you changed the sensors?

 

What other sensors are you talking about what other gaskets it was smoke tested last week and no vacume leaks found so that means the vacume lines are fine and no Crack in the upper manafold. My mechanic is stumped. The only thing I can think of is a bad ecu maybe but I am not sure and donr want to replace it if it is not bad.

 

I think 85e150 is referring to the heated oxygen sensors which it looks like you said were replaced. Those sensors are primarily what the PCM uses to determine if the exhaust is lean or rich. Has your mechanic/technician monitored the datastream of the oxygen sensors to determine if they are responding appropriately? What are the specific diagnostic codes that keep being set? Has the shop checked the PCV elbow that is a bit buried under the intake? Those are a pretty common source of a vacuum leak along with the intake manifold gaskets) and may not be too easy to spot unless they specifically looked for a leak there.

-Rod

 

The codesare p107 and p174 lean bank 1and lean bank 2. The o2 are doing there job the explorer runs well idel is good just can't find why the check engine light won't stay off . Every time I clear the codes with in 20 miles they come back on and the monitors for the o2 and oevape have not yet turned green. I can't have the truck smogged if the check engine light is on or if 2 or monitors is not yet reset so I am open for any suggestions you might have to get this truck Abel to be smogged ty mal11963

 

Please double check the codes. They should have 4 numbers each, so maybe P0107 and P0174, or are they P0171 and P0174? Your description of the codes would suggest P0171 and P0174. How did you confirm that the O2 sensors are doing their job? Are you monitoring the voltage through the data stream of a scan tool or just based on the vehicle running find with a good idle?

If the codes are P0171 and P0174 that could suggest a vacuum leak, or fuel pressure issue, that is common to both banks which is a good start. Then it might be a MAF sensor that is not reading correctly, a crack or connection issue in the intake air tubing between the MAF sensor and the throttle body, a throttle body gasket issue, a fuel pump or fuel filter issue, a vacuum line/fitting that connects at the upper intake, etc. I know you feel like you've checked much of that before, but at least you might be able to narrow down where to look again once you confirm the code numbers.

-Rod

 

You have the codes correct I left the 0 off the map has been replaced the fule pump was replaced 4 years ago the in take is not kneading due to a Crack a smoke test was performed and no vacume leaks found and a Crack in the intake would of shown in the smoke test. My mechanic had the truck on the computer and said the o2's where working fine. The fule filter could use changing it is been about 2 years since it was changed.

 

Has the shop measured the actual fuel pressure at the fuel rail? Have they connected a vacuum gauge to the intake system to monitor how the needle of the gauge changes when the engine is idling as well as when under load? Smoke tests are a pretty good way to find leaks as long as the leaks are in an area that is easy to see. If the mechanic was able to to determine the O2 sensors are working fine, they should also be able to confirm they are consistently reading lean. And if they are tracking with each other, again that should narrow down where the focus should be placed on searching for the issue.

-Rod

 

I dont see any DATA collected on the fuel trims..

 

p0171+p0174 are commonly a symptom of a disconnected\cracked\leaking PCV hose\elbow.

 

My 2001 Sport Trac 4L V6 is having the same issues, P0171 & P0174 constant. Talked to a local mechanic and his over the phone diagnosis, was "when the both O2 sensors are reading lean the PCM is "over compensating" by adding additional fuel over the 20% "normal variance". I purchased a 2-way blue tooth ODB scanner that does 'live reading". During the 'live' reading (engine running) the only sensors that are out of spec are my Engine Coolant Temp Sensor & Air Intake Temp Sensor, both reading HOT.
I'm currently looking for the location of the Air Intake Temp Sensor, as I believe the coolant sensor is in the thermostat housing, and trying to get prices for replacements to see if this will remedy my issues. Also going to look for the driver side PCV hose to see if it "just dun fell off".

Hope this helps.

 

AirIntakeTemp is part of the MassAirFlow\MAFSensor; sends AirTemp & AirVolume signals to PCM that calculates true MassAirFlow.
MAFSensor is located in the AccordianDuct between the AirFilterBox & ThrottleBody.
MAFSensor should be cleaned every 33kMiles\4Yrs with MAFCleaner or ElectricCleaner or RubbingAlcohol+QTips;
do NOT use CarbCleaner or BrakeCleaner, much too harsh.

There are 2 CoolantTempSensors on a 2001 V6~4.0L~SOHC; both mounted in ThermoStatHousing under the ThrottleBody;
One is dedicated\wired to the InstrumentCluster TempGage, the other is dedicate\wired to the Computer\PCM;
they are different both electricly & are plug+socket keyed differently; they are NOT interchangable.
Wires at the TempSensor harness sockets are notorious for insulation damage.

TroubleCodes p0171+p0174 are notoriously caused by cracks\leaks in the rubber PCV Hoses+Elbows; inspect Hose+Tube assemblies
from the right side of the IntakeManifold throat to the PCVValve on the rear of the left ValveCover,
& from the IntakeAirAccordion to the middle of the right ValveCover.

Replacing CoolantTempSensors can easily be done during a CoolantSystem full service, needed every 33kMiles\4Yrs:
* Drain+Flush
* WaterPump RenewedAsNeeded
* Hoses+Clamps RenewedAsNeeded
* ThermoStat & RadCap Renewed
* JunkPlastic ThermoStatHousing replaced with Aluminum version
* JunkPlastic HeaterControlValve renewed or replaced with Aluminum\Stainless version
* JunkPlastic TeeFittings renewed or replaced with Aluminum\Stainless versions
* JunkPlasticTanked 2CoreRadiator renewed or replaced with AllAluminum 3or4Core version
* CoolantRenewed

ExhaustOxSensors & IgnitionPlugs+Wires & OilPressurizedTimingTensioners should be renewed every 100kMiles\12Yrs;
these items inherently wear out & cause low MPG & CatConDamage & TroubleCodes & TimingGuideDamage if not maintained.

Click links below for more info on above items for a 2001 SportTrac:
https://2001fordexplorersporttrac.fa...MAssFlowSensor
https://2001fordexplorersporttrac.fa...Engine_Coolant
https://2001fordexplorersporttrac.fa...an+Clutch+Pump
https://2001fordexplorersporttrac.fa...t_Radiator+Cap
https://2001fordexplorersporttrac.fa...ant_ThermoStat
https://2001fordexplorersporttrac.fa...nt_HeaterValve
https://2001fordexplorersporttrac.fa...sitiveCaseVent
https://2001fordexplorersporttrac.fa..._OxygenSensors
https://2001fordexplorersporttrac.fa...Wires+CoilPack
https://2001fordexplorersporttrac.fa...mingTensioners

Hopefully this helps.