P0101 & P0440 OBDII codes

[pbuehlz]

I am getting the p0101 and p0440 codes. I have been getting these along with the secondary air code since I bought the truck in July. The dealership that I bought it from said that the MAP sensor either works or it doesnt so it is not a bad map sensor because he showed me it hooked up to there scanner and the MAP sensor was working fine. Last fall I removed the AIR Pump and removed about a 1/2 cup of water. I can hear the pump when it does run so I know the pump is not shot. I just took it to the shop last week and got charged $356.33 for a faulty fuel level sensor. I also just bought a new gas cap on Sat because I am told that the gas cap is the main cuprit on the p0101 codes also installed a new air filter. I have NOT just recenty put gas in. I filled up on Sun night and got these codes Mon night and Tues morn. I really dont feel like going to a shop and getting bent over if you know what I mean. Its really starting to hurt.

[j894]

p0101 is has to do with the MAF.
I was getting the same code, replaced the MAF
the problem is now solved

[Sparky2263]

Aside from what we already talked about, here is some info that should help you understand the type of diagnosis necessary.

Or, as John said, put a new MAF sensor on it.

P0101

CIRCUIT DESCRIPTION
The Mass Air Flow (MAF) sensor is an air flow meter. The control module (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/56218937/57612703) supplies the MAF sensor a signal circuit. An ignition positive voltage circuit and a ground circuit are supplied to the MAF sensor by independent circuits. The MAF sensor heats a wire element, or grid, within the MAF sensor in order to maintain a calculated temperature. As inlet air flows across and cools the grid, the MAF sensor increases current flow to the grid in order to maintain the constant grid temperature. The MAF sensor converts the grid current flow into a frequency signal. The control module converts the MAF signal frequency into a grams per second value. During low air flow rates, such as at engine idle, the MAF sensor produces a low frequency signal. During high air flow rates, such as at wide open throttle-road load, the MAF sensor increases the frequency signal. The control module monitors the MAF sensor signal frequency in order to calculate the flow and mass of the air entering the engine.

The VCM monitors the MAF sensor air flow rate and compares this signal to a VCM calculated air flow rate. The calculated air flow is based on engine speed and barometric pressure. The VCM uses the MAP sensor in order to determine the barometric pressure when the ignition key is turned ON but before the engine is cranking or running. This DTC will be set if the MAF sensor signal airflow rate does not match the air flow rate calculated by the VCM.

CONDITIONS FOR RUNNING THE DTC


The engine is running.
No active TP sensor DTCs
No active MAP sensor DTCs
No active EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) DTCs
No active CKP sensor DTCs
No active IAT sensor DTCs
DTC P0401 not active
DTCs P0102 and P0103 not active
The system voltage is between 11-16 volts .
The canister purge duty cycle is less than 99 percent .
The TP sensor voltage is steady.
The EGR (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34858149) duty cycle is less than 90 percent .
The EGR (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34858149) pintle position is less than 90 percent
The throttle position is less than 90 percent .
The above conditions met for more than 2 seconds .
CONDITIONS FOR SETTING THE DTC



The actual MAF value is not equal to the calculated MAF.
The above condition exists for more than 5 seconds .
ACTION TAKEN WHEN THE DTC SETS



The control module (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/56218937/57612703) illuminates the Malfunction Indicator Lamp (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) (MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480)) if a failure is detected during 2 consecutive key cycles.
The control module (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/56218937/57612703) sets the DTC and records the operating conditions at the time the diagnostic failed. The failure information is stored in the scan tool Freeze Frame and Failure Records.
CONDITIONS FOR CLEARING THE MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) OR DTC



The control module (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/56218937/57612703) turns OFF the MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) after 3 consecutive drive trips when the test has run and passed.
A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle.
Use a scan tool in order to clear the DTCs.
DIAGNOSTIC AIDS
Check for the following conditions:



A misrouted harness - Inspect the MAF sensor harness in order to ensure that it is not routed too close to high voltage wires such as spark plug (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34859584/58828691) leads.
A damaged harness - Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving the connectors and the wiring harnesses related to the MAF sensor. A change in the display indicates the location of the fault.
A plugged intake air duct or a dirty air filter element (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34872087). A wide open throttle acceleration from a stop should cause the mass air flow displayed on a scan tool to increase from about 4-7 gm/s at idle to 100 gm/s or more at the time of the 1-2 shift. If not, check for a restriction.
An intermittent may be caused by any of the following conditions:



A poor connection
Rubbed through wire insulation
A broken wire inside the insulation
Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for intermittent and Poor Connections in Diagrams.

If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Diagrams.


P0440

CIRCUIT DESCRIPTION
The evaporative system includes the following components:


The fuel tank (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34859372)
The EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent solenoid
The fuel tank pressure sensor (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/56194619)
The fuel pipes and hoses The vapor lines
The fuel cap
The evaporative emission canister
The purge lines
The EVAP purge solenoid
The evaporative leak detection diagnostic strategy is based on applying a vacuum to the EVAP system and monitoring the vacuum decay rate. The Vehicle Control Module (VCM) monitors the vacuum level via the fuel tank pressure sensor (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/56194619) input. At an appropriate time, the EVAP purge solenoid and the EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent solenoid turn ON, allowing the engine vacuum to draw a small vacuum on the entire evaporative emission system. If a sufficient vacuum level cannot be achieved, a large leak or an EVAP system malfunction is indicated. The following conditions can cause this problem:



A disconnected or malfunctioning fuel tank pressure sensor (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/56194619)
A missing, malfunctioning, improperly installed, or loose fuel cap
A disconnected, damaged, pinched, or blocked EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) purge line
A disconnected or damaged EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent hose
A disconnected, damaged, pinched, or blocked fuel tank (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34859372) vapor line
A disconnected or malfunctioning EVAP purge solenoid
A disconnected or malfunctioning EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent solenoid
An open ignition feed circuit to the EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent or purge solenoid
A damaged EVAP canister
A leaking fuel sender assembly O-ring
A leaking fuel tank (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34859372) or fuel filler neck (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/81873561)
Any of the above conditions can set a DTC P0440.

CONDITIONS FOR RUNNING THE DTC



No active MAP sensor DTCs
No active TP sensor DTCs
No active VS sensor DTCs
No active O2 sensor DTCs
No active ECT sensor DTCs
No active IAT sensor DTCs
DTC P0125 not active
The system voltage is between 10-17 volts
The fuel level is between 12.5-87 percent .
The ECT is between 4°C-30°C (39°F-86°F)
The IAT is between 4°C-30°C (39°F-86°F)
The cold start temperature difference (ECT minus IAT) is less than 1.5°C when the IAT is more than the ECT or 8°C when the ECT is more than the IAT
The BARO is more than 73 kPa
CONDITIONS FOR SETTING THE DTC
The EVAP system is unable to generate a vacuum more than a calibrated value over a specified period of time.

ACTION TAKEN WHEN THE DTC SETS



This is a type A DTC that behaves like a B type, in which the VCM illuminates the MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) after the second key cycle.
The VCM stores the conditions that were present when the DTC sets as a Freeze Frame/Failure Records data.
CONDITIONS FOR CLEARING THE MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) OR DTC



The control module (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/56218937/57612703) turns OFF the MIL (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/34857480) after 3 consecutive drive trips when the test has run and passed.
A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle.
Use a scan tool in order to clear the DTCs.
DIAGNOSTIC AIDS

IMPORTANT: An accurate indication of fuel level is required for the VCM to properly pass or fail this DTC. Always diagnose fuel level sensor (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/101367480) DTCs before performing this DTCs diagnostic table. Always check for fuel level sensor DTCs stored in history.

Check for the following conditions:



A loose, missing, damaged, incorrect or improperly installed fuel cap
Missing or damaged O-rings at EVAP canister fuel vapor and purge line fittings
A cracked or punctured EVAP canister
A damaged or disconnected EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) purge line, vent hose or fuel tank (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34859372) vapor line
Incorrectly routed or damaged EVAP system purge and vapor lines
A poor connection at the VCM. Inspect the harness connectors for the following conditions:
Backed out terminals
Improper mating
Broken locks
Improperly formed or damaged terminals
poor terminal to wire connection
A damaged harness - Inspect the wiring harness to the EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) vent solenoid, EVAP purge solenoid and the fuel tank pressure sensor (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857030/56194619) for an intermittent, open or short circuit.
A kinked, pinched or plugged EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077) purge or fuel tank (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34858641/34859372) vapor line - Verify that the lines are not restricted.
Refer to Evaporative Emission (EVAP (http://motoralldata.com/alldata/MOTOR~V31129501~C37357~R0~OD~N/0/77993956/78154671/92727709/92727711/34853741/34857029/34857699/34872077)) System Cleaning before starting repairs. Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

[j894]

Forgot to mention, for me the SES light come on randomly and would throw that code. It wasnt constantly on. Somtimes it would come on for 5-10 minutes, other times days. Didnt really seem to run to much different.

[pbuehlz]

Just Checked and snugged all the vacuum hoses and reseated the Cold air intake hose around the MAF Sensor. Truck had just a slight miss before that and not sure if it is just today or if it is just me but the miss seems to be gone. Cleared the codes and I will keep my fingers crossed. Just put gas in on the way home and got 239 miles on 13 gallons of gas. Thats 18.38 mpg up from the regular 17-17.5 I usually get. Not sure if I have sea foam to thank for that but will keep an eye on it.