Dtc p0451, p0452 or p0453 is recorded by the ecm when the vapor pressure sensor malfunctions.
P0451
The ecm senses pressure in the fuel tank using the vapor pressure sensor. The ecm supplies the sensor with a regulated 5 v reference–voltage and the sensor returns a signal voltage between 0.5 V and 4.5 V according to the pressure level in the fuel tank.
When the pressure in the fuel tank is low, the output voltage of the vapor pressure sensor is low. When it is high, the output voltage is high.
For this dtc p0451, the ecm checks for a ”noisy” sensor or a ”stuck” sensor.
The ecm checks for the ”noisy” sensor by monitoring the fuel tank pressures when the vehicle is stationary and there should be little variation in the tank pressure. If the indicated pressure varies beyond specified limits, the ecm will illuminate the mil and a dtc is set.
The ecm checks for the ”stuck” sensor by monitoring the fuel tank pressure for an extended time period.
If the indicated pressure does not change over this period, the ecm will conclude that the fuel tank pressure sensor is malfunctioning. The ecm will illuminate the mil and a dtc is set.
P0452 and p0453
The ecm senses pressure in the fuel tank using the vapor pressure sensor. The ecm supplies the sensor with a regulated 5 v reference–voltage and the sensor returns a signal voltage between 0.5 V and 4.5 V according to the pressure level in the fuel tank.
When the pressure in the fuel tank is low, the output voltage of the vapor pressure sensor is low. When it is high, the output voltage is high.
If the output voltage of the vapor pressure sensor is out of the normal range, the ecm will determine that there is a malfunction in the sensor or sensor circuit.
When pressure indicated by the vapor pressure sensor deviates below –3.999 Kpa (–30 mmhg) or above 1.999 Kpa (15 mmhg), the ecm interprets this as a malfunction in the vapor pressure sensor. The ecm will turn on the mil and a dtc will be set.
Monitor strategy
P0451
P0452 and p0453
Typical enabling conditions
P0451
P0452 and p0453
Typical malfunction thresholds
P0451
P0452 and p0453
Wiring diagram
Refer to dtc no. P0441
Adjusting the mirrors
Make sure that you can see backward clearly by adjusting the inside and outside
rear view mirrors properly.
CAUTION
Observe the following precautions.
Failure to do so may result in death or serious injury.
●Do not adjust the position of the driver’s seat while driving.
Doing so could c ...
Inspection procedure
Hint:
perform the troubleshooting of dtc p0335 first. If no trouble is
found, troubleshoot the engine mechanical
systems.
Read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records
the engine conditions when a malfunction is detected. When tr ...
Replacement
1. Work for preventing gasoline from spilling out
2. Remove engine under cover rh
3. Drain coolant
4. Remove front wheel rh
5. Remove cylinder head cover no.2
Remove the 2 nuts, 2 clips and cylinder head cover.
6. Remove air cleaner hose no.1
loosen the 2 air cleaner hose ...