Lexus SC300 / Lexus SC400. Manual — part 349

(b) Disconnect the following hoses:

(1) Water bypass hose from IAC valve
(2) California:

Vacuum hose from throttle body

(3) Except

California:

3 vacuum hoses from throttle body

(c) Remove the 2 bolts and 2 nuts, and disconnect the throttle

body from the air intake chamber.

(d) Disconnect the following hoses, and remove the throttle

body.
(1) PCV hose from throttle body
(2) Water bypass hose from throttle body

(e) Remove the throttle body gasket.

17. REMOVE RH CYLINDER HEAD COVER
(a) Disconnect the No.2 high–tension cord from the cord clamp

on the front high–tension cord clamp.

(b) Remove the 2 bolts holding the high–tension cord clamps to

the cylinder head cover.

(c) Disconnect

the 5 high–tension cords from the front side of the

front high–tension cord clamp.

(d) Disconnect the front high–tension cord clamp from the lower

high–tension cord cover.

–

1UZ–FE ENGINE

ENGINE MECHANICAL

EG–17

(e) Disconnect the 4 high–tension cords together with the front

and rear high–tension cord clamps from the spark plugs.

NOTICE: Pulling on or bending the cords may damage the con-

ductor inside.

(f)

Remove the 8 bolts, seal washers, cylinder head cover and
gasket.

18. REMOVE LH CYLINDER HEAD COVER
(a) Disconnect the No.1 high–tension cord from the cord clamp

on the front high–tension cord clamp.

(b) Remove the 2 bolts holding the high–tension cord clamps to

the cylinder head cover.

(c) Disconnect

the 5 high–tension cords from the front side of the

front high–tension cord clamp.

(d) Disconnect the front high–tension cord clamp from the lower

high–tension cord cover.

(e) Disconnect the 4 high–tension cords together with the front

and rear high–tension cord clamps from the spark plugs.

NOTICE: Pulling on or bending the cords may damage the con-

ductor inside.

(f)

Disconnect the engine wire protector from the 2 brackets on
the delivery pipe.

(g) Disconnect the 4 injector connectors.

EG–18

–

1UZ–FE ENGINE

ENGINE MECHANICAL

(h) Disconnect the 2 engine wire connectors.

(i)

Remove the 8 bolts, seal washers, cylinder head cover and
gasket.

19. SET NO.1 CYLINDER TO TDC/COMPRESSION
(a) Turn the crankshaft pulley, and align its groove with timing

mark “0” of the No.1 timing belt cover.

(b) Check that the timing marks of the camshaft timing pulleys

and timing belt rear plates aligned.
If not, turn the crankshaft 1 revolution (360

°

) and align the

mark as above.

–

1UZ–FE ENGINE

ENGINE MECHANICAL

EG–19

20. INSPECT VALVE CLEARANCE
(a) Check only the valves indicated.

•

Using a feeler gauge, measure the clearance between
the valve lifter and camshaft

•

Record the out–of–specification valve clearance
measurements. They will be used later to determine the
required replacement adjusting shim.

Valve clearance (Cold):

Intake

0.15 – 0.25 mm (0.006 – 0.010 in.)

Exhaust

0.25 – 0.35 mm (0.010 – 0.014 in.)

(b) Turn the crankshaft 1 revolution (360

) and align the mark as

above. (See procedure in step 8)

(c) Check

only the valves indicated as shown. Measure the valve

clearance. (See procedure in step (a))

21. REMOVE THEFT DETERRENT HORN
(a) Disconnect the connector.
(b) Remove the bolt and theft deterrent horn.

HINT: Remove the deterrent horn when the valve clearance
is adjusted for the front portion of the exhaust camshaft on
the LH cylinder head.

EG–20

–

1UZ–FE ENGINE

ENGINE MECHANICAL