Help with dailly driver code P0450
#1
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I need to get the SES light off so I can pass inspection. Took the car to Vato Zone today and it threw 1 code, P0450. Description:
EVAP system pressure sensor malfunction
Probable cause
1. Open or short circuit condition
2. Poor electrical connection
3. Blocked canister or failed vent solenoid
4. Faulty EVAP pressure sensor
Anyone ever experiecne this code, or have any idea whats throwing it? Im hoping is just a cheap easy fix like a sensor somehwere. Thanks in advnace
Charlie
EVAP system pressure sensor malfunction
Probable cause
1. Open or short circuit condition
2. Poor electrical connection
3. Blocked canister or failed vent solenoid
4. Faulty EVAP pressure sensor
Anyone ever experiecne this code, or have any idea whats throwing it? Im hoping is just a cheap easy fix like a sensor somehwere. Thanks in advnace
Charlie
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Found some info for ya
Symptoms
Check Engine Light will illuminate
In most cases, there are no adverse conditions noticed by the driver
In some cases, there may be a noticeable fuel odor caused by the release of fuel vapors
Common Problems That Trigger the P0450 Code
Defective Fuel Tank Sending Unit
Defective or damaged Fuel Tank
Defective Fuel Tank Pressure Sensor, wiring, or computer
Common Misdiagnoses
Fuel Cap
Evaporative Purge Valve
Evaporative Vent Valve
Polluting Gases Expelled
HCs (Hydrocarbons): Unburned droplets of raw fuel that smell, affect breathing, and contribute to smog
The Basics
The Fuel Tank Pressure Sensor is a device that tracks any positive or negative pressure changes in the Fuel Storage or Evaporative Control (EVAP) system. It constantly relays this pressure information to the Power Train Control Module (PCM). The Fuel Tank Pressure Sensor is located on top of the Fuel Tank, or on or near the Fuel Pump and Fuel Gauge Module.
Want to Learn More?
The Evaporative Control system Pressure Sensor code sets when the readings of the Pressure Sensor remain at a fixed value and do not change for ten seconds of vehicle operation after a cold start.
P0450 Diagnostic Theory for Shops and Technicians
The Code P0450 indicates that the Evaporative Pressure Sensor output value is not changing during the EVAP Monitor test and/or the operation of the vehicle. This code uses "two trip" logic, which means that the fault condition must be present during two successive cold starts and vehicle operation.
Common Tests for the Evaluating the Fuel Tank Pressure Sensor
Retrieve the code and write down the freeze frame information to be used as a baseline to test and verify any repair.
Pay very close attention to the Fuel Tank Pressure readings by observing its data stream on a scan tool. Does the Fuel Tank Pressure Sensor work properly? If it doesn't, the system will think that no vacuum is being created when, in fact, there is a vacuum being created that the Fuel Tank Pressure Sensor is unable to read. The Fuel Tank Pressure Sensor is the primary feedback sensor that the Power Train Computer relies on for the leak test data.
Inspect and test the Fuel Pressure Sensor wiring. Verify that there is a 5-volt reference signal from the PCM, a good ground, as well as a good signal return circuit to the PCM.
While observing the data stream change (or lack there of) on a scan tool, test the Pressure Sensor with a Vacuum Gauge while it is connected to the wiring harness.
If all of the above test results are within spec, then the problem may reside in the PCM itself.
Symptoms
Check Engine Light will illuminate
In most cases, there are no adverse conditions noticed by the driver
In some cases, there may be a noticeable fuel odor caused by the release of fuel vapors
Common Problems That Trigger the P0450 Code
Defective Fuel Tank Sending Unit
Defective or damaged Fuel Tank
Defective Fuel Tank Pressure Sensor, wiring, or computer
Common Misdiagnoses
Fuel Cap
Evaporative Purge Valve
Evaporative Vent Valve
Polluting Gases Expelled
HCs (Hydrocarbons): Unburned droplets of raw fuel that smell, affect breathing, and contribute to smog
The Basics
The Fuel Tank Pressure Sensor is a device that tracks any positive or negative pressure changes in the Fuel Storage or Evaporative Control (EVAP) system. It constantly relays this pressure information to the Power Train Control Module (PCM). The Fuel Tank Pressure Sensor is located on top of the Fuel Tank, or on or near the Fuel Pump and Fuel Gauge Module.
Want to Learn More?
The Evaporative Control system Pressure Sensor code sets when the readings of the Pressure Sensor remain at a fixed value and do not change for ten seconds of vehicle operation after a cold start.
P0450 Diagnostic Theory for Shops and Technicians
The Code P0450 indicates that the Evaporative Pressure Sensor output value is not changing during the EVAP Monitor test and/or the operation of the vehicle. This code uses "two trip" logic, which means that the fault condition must be present during two successive cold starts and vehicle operation.
Common Tests for the Evaluating the Fuel Tank Pressure Sensor
Retrieve the code and write down the freeze frame information to be used as a baseline to test and verify any repair.
Pay very close attention to the Fuel Tank Pressure readings by observing its data stream on a scan tool. Does the Fuel Tank Pressure Sensor work properly? If it doesn't, the system will think that no vacuum is being created when, in fact, there is a vacuum being created that the Fuel Tank Pressure Sensor is unable to read. The Fuel Tank Pressure Sensor is the primary feedback sensor that the Power Train Computer relies on for the leak test data.
Inspect and test the Fuel Pressure Sensor wiring. Verify that there is a 5-volt reference signal from the PCM, a good ground, as well as a good signal return circuit to the PCM.
While observing the data stream change (or lack there of) on a scan tool, test the Pressure Sensor with a Vacuum Gauge while it is connected to the wiring harness.
If all of the above test results are within spec, then the problem may reside in the PCM itself.
#6
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Its been on for some time now, so Im pretty sure its not the gas cap issue. I make sure to hear it click 3-4 times every time I fill up...I found this on ebay
http://cgi.ebay.com/ebaymotors/SMP-S...item27bd99dd76
Is this the sensor that the code is describing?
http://cgi.ebay.com/ebaymotors/SMP-S...item27bd99dd76
Is this the sensor that the code is describing?
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Its been on for some time now, so Im pretty sure its not the gas cap issue. I make sure to hear it click 3-4 times every time I fill up...I found this on ebay
http://cgi.ebay.com/ebaymotors/SMP-S...item27bd99dd76
Is this the sensor that the code is describing?
http://cgi.ebay.com/ebaymotors/SMP-S...item27bd99dd76
Is this the sensor that the code is describing?