Toyota Tundra. Manual — part 2195

Fig. 6: Inserting Compression Gauge Into Spark Plug Hole
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

4. If the cylinder compression is low in one or more cylinders, pour a small amount of engine

oil into the cylinder with low compression through its spark plug hole. Then inspect the
cylinder compression pressure again.

HINT:



If adding oil helps boost the compression, it is likely that the piston rings and/or
cylinder bore are worn or damaged.



If pressure stays low, a valve may be stuck or seated improperly, or there may be
leakage in the gasket.

i. Install the 8 spark plugs.

j. Install the 8 ignition coils with the 8 bolts.

k. Connect the 2 injector connectors and 8 ignition coil connectors.

l. Install the air cleaner cap.

m. Install the air cleaner hose.

n. Install the V-bank cover.

4. INSPECT CO/HC

NOTE:



Always use a fully charged battery to obtain an engine
speed of 250 RPM or more.



This measurement must be done as quickly as possible.

2009 Toyota Tundra

2009 ENGINE Engine Mechanical (3UR-FBE) - Tundra

HINT:

This check is used only to determine whether or not the idle CO/HC complies with regulations.

a. Start the engine.

b. Keep the engine speed at 2500 RPM for approximately 180 seconds.

c. Insert the CO/HC meter testing probe at least 40 cm (1.31 ft.) into the tailpipe during idling.

Fig. 7: Checking CO/HC
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

d. Immediately check CO/HC concentration at idle and/or 2500 RPM.

HINT:

When performing the 2 mode (2500 RPM and idle) test, follow the measurement order prescribed
by the applicable local regulations.

e. If the CO/HC concentration does not comply with the regulations, troubleshoot in the order given

below.

1. Check the A/F sensor operation (See ON-VEHICLE INSPECTION ) and heated oxygen

sensor operation (See ON-VEHICLE INSPECTION ).

2. See the table below for possible causes, and then inspect and correct the applicable causes if

necessary.

TROUBLE SYMPTOM REFERENCE CHART

CO

HC

Symptom

Cause

Normal High Rough idle

1. Faulty ignitions:



Incorrect timing



Plugs (contaminated, shorted or gaps
are defective)

2. Incorrect valve clearance

3. Leaky intake and exhaust valves

4. Leaky cylinder

2009 Toyota Tundra

2009 ENGINE Engine Mechanical (3UR-FBE) - Tundra

DRIVE BELT

COMPONENTS

Fig. 8: Identifying Drive Belt Components With Torque Specifications
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

ON-VEHICLE INSPECTION

1. INSPECT FAN AND GENERATOR V BELT

a. Check the belt for wear, cracks or other signs of damage.

If any of the following defects is found, replace the fan and generator V belt.



The belt is cracked.



The belt is worn out to the extent that the cords are exposed.

Low High

Rough idle (Fluctuating HC
reading)

1. Vacuum leaks:



PCV hose



Intake manifold



Throttle body



Brake booster line

2. Lean mixture causing misfire

High High

Rough idle (Black smoke
from exhaust)

1. Restricted air filter

2. Faulty SFI system:



Faulty pressure regulator



Defective ECT sensor



Faulty ECM - Faulty injectors



Faulty throttle position sensor



Faulty MAF meter

2009 Toyota Tundra

2009 ENGINE Engine Mechanical (3UR-FBE) - Tundra



The belt has chunks missing from the ribs.

Fig. 9: Identifying Damage Belt
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Check that the belt fits properly in the ribbed grooves.

HINT:

Check with your hand to confirm that the belt has not slipped out of the grooves on the bottom of
the pulley. If it has slipped out, replace the fan and generator V belt. Install a new fan and generator
V belt correctly.

2. INSPECT V-RIBBED BELT TENSIONER ASSEMBLY

a. Check that nothing gets caught in the tensioner by turning it clockwise and counterclockwise. If the

result is not as specified condition, replace the tensioner.

REMOVAL

1. REMOVE V-BANK COVER SUB-ASSEMBLY (See REMOVAL )

2. REMOVE NO. 1 ENGINE UNDER COVER (See REPLACEMENT )

3. REMOVE FAN AND GENERATOR V BELT

a. While turning the belt tensioner counterclockwise, align the service hole for the belt tensioner and

the belt tensioner fixing position, and then insert a bar of Ø 5 mm (0.197 in.) into the service hole
to fix the belt tensioner in place.

HINT:

The pulley bolt for the belt tensioner has a left-hand thread.

2009 Toyota Tundra

2009 ENGINE Engine Mechanical (3UR-FBE) - Tundra