Toyota Sequoia (2005). Manual - part 170

A23505

Purge VSV

Vent Valve

Vacuum Pump

EVAP Pressure

Positive

ON: Open

Negative

ON

ON

Steps

(Reference)

ON

OFF: Closed

OFF: Vent

ON: Closed

Time

60

sec

5/5

Leak Pressure

First 0.02 inch

Standard

Gross Leak

Small Leak

No Leak

Leak Pressure

Second 0.02 inch

Standard x 0.2

–

DIAGNOSTICS

ENGINE

DI–475

669

10

Perform EVAP system step 5/5 check.

(a)

Check the EVAP pressure in step 5/5.

(b)

Compare the EVAP pressure in step 3/5 and the second 0.02 inch leak pressure standard (step 5/5).
Result:

DTCs*

Test Results

Suspected Trouble Areas

Proceed To



EVAP pressure (step 3/5) lower than the second
0.02 inch leak pressure standard (step 5/5)

Not yet determined (no leakage from EVAP system)

A

P0441 and

P0455

EVAP pressure (step 3/5) higher than [second 0.02
inch leak pressure standard (step 5/5) x 0.2]

Purge VSV stuck open

EVAP gross leak

B

P0456

EVAP pressure (step 3/5) higher than second 0.02
inch leak pressure standard (step 5/5)

EVAP small leak

B

*: The DTCs relating to the EVAP system displayed on a hand–held tester when checking.

A

Go to step 36.

B

Go to step 12.

A23506

ON

0.02 inch Orifice High–flow

3/5

ON

ON

Purge VSV

Vent Valve

Vacuum Pump

EVAP Pressure

Positive

Negative

Steps

(Reference)

Time

ON: Open
OFF: Closed

OFF: Vent

ON: Closed

Leak Pressure

0.02 inch

Standard

2/5

Vacuum Pump Stuck OFF

Within 15 minutes

DI–476

–

DIAGNOSTICS

ENGINE

670

11

Perform EVAP system step 3/5 check.

(a)

Check the EVAP pressure in step 3/5.
Result:

DTCs*

Test Results

Suspected Trouble Areas

Proceed To



EVAP pressure less than [0.02 inch leak pressure
standard x 0.2]

0.02 inch orifice high–flow

A



EVAP pressure more than [0.02 inch leak pressure
standard x 0.2]

Vacuum pump stuck OFF

B

*: The DTCs relating to the EVAP system displayed on a hand–held tester when checking.
HINT:
The 0.02 inch leak pressure standard is the value determined in step 2/5.

A

Go to step 30.

B

Go to step 23.

B17420

Hose

Purge VSV

–

DIAGNOSTICS

ENGINE

DI–477

671

12

Perform active test of purge VSV.

PREPARATION:
(a)

On the hand–held tester, select the following menu items:
DIAGNOSIS / ENHANCED OBD II/ ACTIVE TEST /
EVAP VSV.

(b)

Disconnect the hose (connected to the canister) from the
purge VSV.

(c)

Start the engine.

CHECK:
(a)

On the tester, turn off the purge VSV (EVAP VSV: OFF).

(b)

Use your finger to confirm that the purge VSV has no suc-
tion.

(c)

Using the tester, turn on the purge VSV (EVAP VSV: ON).

(d)

Use your finger to confirm that the purge VSV has suction.

RESULT:

Test Results

Suspected Trouble Areas

Proceed To

No suction when purge VSV turned OFF, and suction applied
when tuned ON

Purge VSV normal

A

Suction applied when purge VSV turned OFF

Purge VSV stuck open

B

No suction when purge VSV turned ON

Purge VSV stuck closed

Problems with EVAP hose between purge VSV and throttle
body

C

B

Go to step 14.

C

Go to step 15.

A

DI–478

–

DIAGNOSTICS

ENGINE

672

13

Check fuel tank cap.

CHECK:
(a)

Check that the fuel tank cap is correctly installed.

(b)

Confirm that the fuel tank cap is tightened until a few click sounds are heard.

HINT:
If an EVAP tester is available, check the fuel tank cap using the tester.

(1)

Remove the fuel tank cap and install it onto a fuel tank cap adaptor.

(2)

Connect an EVAP tester pump hose to the adaptor, and pressurize to 3.2 to 3.7 kPa (24 to 28
mmHg) using an EVAP tester pump.

(3)

Seal the adaptor and wait for 2 minutes.

(4)

Check the pressure. If the pressure is 2 kPa (15 mmHg) or more, the fuel tank cap is normal.

(5)

Reinstall the fuel tank cap.

PREPARATION:

Test Results

Suspected Trouble Areas

Proceed To

Fuel tank cap correctly installed



A

Fuel tank cap loose

Fuel tank cap improperly installed

Defective fuel tank cap

Fuel tank cap does not meet OEM specifications

B

No fuel tank cap



C

A

Go to step 29.

B

Go to step 27.

C

Go to step 28.