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Air Suction System Toyota Tercel L30

Testing & Diagnostics 13 illustrations ~1143 words

DESCRIPTION

Air suction system uses exhaust gas pulses to draw air into the exhaust manifold or catalytic converter to help complete oxidation of emissions. (Scheme 12)- (Scheme 18). The air suction system on California Pickup (Carbureted) models is computer controlled and therefore is closely tied with the carburetor/fuel feedback control system. (Scheme 19)- (Scheme 21). See appropriate CEC article in the COMPUTERIZED ENGINE CONTROLS section. for information and testing of vehicle speed sensor, temperature switches, and oxygen sensor.

OPERATION

Air is drawn through the filter and air suction valve into exhaust manifold or into catalytic converter. Operation of air suction system on California Pickups is computer controlled.

Federal

Check condition of all hoses and tubes. Start engine. On all Corolla models, remove air cleaner cap and ensure a bubbling noise can be heard from air suction valve inlet. On Tercel Wagon models, ensure air is drawn into inlet pipe.

California

Check condition of all hoses and tubes. Start engine. Disconnect vacuum hose from shutoff valve and plug end of hose. Remove air cleaner cap and start engine. Reconnect vacuum hose to shutoff valve. Ensure a bubbling noise is heard from air suction valve inlet within 2-6 seconds. Reinstall air cleaner cap.

Scheme 12

Scheme 12: California
Scheme 12: California

Scheme 13

Scheme 13
Scheme 13

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15
Scheme 15

Scheme 16

Scheme 16
Scheme 16

Scheme 17

Scheme 17
Scheme 17

Scheme 18

Scheme 18
Scheme 18

Scheme 19

Scheme 19
Scheme 19

Scheme 20

Scheme 20
Scheme 20

Scheme 21

Scheme 21
Scheme 21

California (Carbureted)

  1. Check condition of all hoses and tubes. Ensure coolant temperature is below 43°F (6°C). Start engine and ensure a bubbling noise is not heard from Electronic Air Control Valve (EACV).
  2. Warm engine until coolant temperature is between 64-109°F (18-43°C). Maintain engine speed at 1390 RPM and check that a bubbling noise is heard from EACV.
  3. Continue to run engine until coolant temperature is above 131°F (55°C). Maintain engine speed at 1390 RPM and check that a bubbling noise is intermittently heard from EACV.
  4. Allow engine to return to idle and check that a bubbling noise is heard from EACV. With coolant temperature above 64°F (18°C) and engine under heavy load, disconnect vacuum hose from vacuum switch and plug end of hose. Ensure a bubbling noise is not heard from EACV.

Fuel Injected (2.4L)

  1. Check condition of all hoses and tubes. With coolant temperature below 86°F (30°C), disconnect air suction hose from air cleaner case. (Scheme 20) Ensure a bubbling noise is heard from hose at idle.
  2. Warm engine to 104°F (40°C). With engine at idle, ensure bubbling noise is not heard from hose. Race engine and quickly close throttle valve. Ensure bubbling noise momentarily stops.

Fuel Injected (3.0L)

  1. Check condition of all hoses and tubes. With coolant temperature below 95°F (35°C), disconnect No. 1 air suction hose from air pipe. (Scheme 21) Ensure a bubbling noise is heard from air pipe at idle.
  2. Warm engine to above 95°F (35°C). With engine at idle, ensure bubbling noise is not heard from air pipe. Race engine above 2000 RPM. Ensure a bubbling noise is heard within 2-6 seconds.

Scheme 22

Scheme 22
Scheme 22

Scheme 23

Scheme 23
Scheme 23

TERCEL

  1. Check condition of all hoses and tubes. On Federal models, disconnect air suction hose from air cleaner cap. Start engine. With engine idling, check that a bubbling noise is heard from end of hose.
  2. On California models, disconnect and plug vacuum hose from shutoff valve. Disconnect air suction hose from air cleaner cap. Start engine. With engine idling, check that a bubbling noise is heard from end of hose.
  3. Reconnect air suction hose to air cleaner cap. Reconnect vacuum hose to shutoff valve and check that a bubbling noise is heard from valve inlet within 2-6 seconds.

Corolla (Carbureted), Corolla FX & Tercel (Federal)

  1. Ensure no air flows through valve when blowing on converter side of valve. Ensure that air flows through valve when air is sucked.

Corolla (Carbureted), Corolla FX & Tercel (California)

Apply vacuum to diaphragm. Ensure air flows from filter side of valve to outlet port. Air should not flow from outlet port to filter side of valve. Release vacuum on diaphragm. Ensure very little air flows from filter side of valve to outlet pipe.

Pickup (California Carbureted)

Ensure no air flows through valve when blowing on converter side of valve. Ensure that air flows through valve when air is sucked.

Pickup (All EFI)

Apply vacuum to reed valve diaphragm. Blow air into reed valve pipe and ensure reed valve is open. Release vacuum and ensure reed valve is closed.

Tercel Wagon (Federal)

  1. On FWD manual transmission models, check that no air flows through valve when blowing on converter side of valve. Ensure that air flows through valve when air is sucked.
  2. On automatic transmission and 4WD models, check that no air flows through valve when air is sucked from filter side. Ensure that air flows through valve when air is blown from filter side.
  1. Disconnect air suction hose from EACV. Unplug connector from No. 2 temperature switch and ground it. Ensure a bubbling noise is not heard from EACV. Reconnect No. 2 temperature switch.
  2. Unplug connector from No. 1 temperature switch and ground it. Maintain engine speed above 1390 RPM and check that a bubbling noise is heard from EACV. If not, replace EACV. Reconnect No. 1 temperature switch.

Tercel Wagon (California)

Apply vacuum to shutoff valve diaphragm. Ensure that air flows from filter side of valve to outlet pipe, and that air does not flow from outlet pipe to filter side of valve. Release vacuum on diaphragm. Check that very little air flows from filter side of valve to outlet pipe.

  1. To test vacuum switch No. 1, use an ohmmeter to check continuity between switch terminal and switch body. Ohmmeter should indicate continuity. Warm engine to normal operating temperature and check continuity between switch terminal and switch body. Ohmmeter should indicate infinity (no continuity).
  2. To test vacuum switch No. 2, use an ohmmeter to check continuity between switch terminal and switch body. Ohmmeter should indicate infinity (no continuity). Warm engine to normal operating temperature and check continuity between switch terminal and switch body. Ohmmeter should indicate continuity.
  1. Connect battery voltage to vacuum control valve. (Scheme 24) Blow into port "E" and ensure air comes out of port "G". Disconnect battery voltage and blow into port "E". Air should come out of air filter. If not to specification, replace VSV.
  2. Using an ohmmeter, ensure no continuity is present between VSV terminals and VSV body. Measure resistance between VSV terminals. Resistance should be 30-50 ohms at 68°F (20°C).

Scheme 24

Scheme 24
Scheme 24

Ensure air flows from Orange port to Black port. Air should not flow from Black port to Orange port.

California Corolla (All Models), Tercel, Tercel Wagon & Federal Pickup

Check VTV by blowing air into each side. Verify air flows without resistance from Black side of valve to other (Brown, Blue or Gray) side of valve. Air should flow with difficulty from colored side of valve to Black side. If not, replace valve.

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