Acura 3.5 RL, Manual

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Throttle Body
Description
The throttle body is a single-barrel side-draft type. The
lower portion of the throttle valve is heated by engine
coolant from the cylinder head. The idle adjusting screw,
which increases/decreases bypass air, and the Evapora-
tive Emission (EVAP) Canister port are located on the top
of the throttle body.
THROTTLE
POSITION
(TP)
SENSOR
IDLE ADJUSTING
SCREW
THROTTLE
VALVE
THROTTLE
STOP
SCREW
(Do not adjust.)
Inspection
1. Disconnect the vacuum hose (to the EVAP canister)
from the top of the throttle body; connect a vacuum
gauge to the throttle body.
VACUUM PUMP/GAUGE, 0 - 30 in.Hg
A973X - 041 - XXXXX
2. Allow the engine to idle, and check that the gauge
indicates no vacuum.
If there is vacuum, check the throttle cable (see
page
11-154 ).
3. Check that vacuum is indicated on the gauge when
the throttle is opened slightly from idle.
If the gauge indicates no vacuum, check the throttle
body port. If the throttle body port is clogged, clean
it with carburetor cleaner.
4. Stop the engine, and check that the throttle cable
operates smoothly without binding or sticking.
If there are any abnormalities in the above steps,
check for.
• Excessive wear or play in the throttle valve shaft.
• Sticky or binding throttle lever at full close posi-
tion.
• Clearance between throttle stop screw and throt-
tle lever at the fully closed position.
There should be
no clearance.
THROTTLE LEVER
THROTTLE
LEVER
THROTTLE STOP SCREW
(Do not adjust.)
Replace the throttle body if there is excessive play
in the throttle valve shaft or if the shaft is binding or
sticking.