Section 08 ENGINE MANAGEMENT (4-TEC)
Subsection 02 (COMPONENT INSPECTION AND ADJUSTMENT)
Mechanical Inspection
Check that the throttle plate moves freely and
smoothly when depressing throttle lever. Take
this opportunity to lubricate the throttle cable.
IMPORTANT: The throttle body is designed to be
tamper proof. Changing the idle stop or modify-
ing it in any way will not increase performance or
change the idle speed but may cause poor starta-
bility and erratic idling.
Before replacing any part, check the following as
these could be causing the fault. Perform the test
while the engine is not running.
– Throttle cable adjustment too tight. Not return-
ing fully to idle stop.
– Throttle body idle set screw is loose or worn.
– TPS is loose.
– Idle bypass valve is loose.
– Corroded or damaged wiring or connectors.
– Throttle body has been replaced and the Closed
Throttle and Idle Actuator reset has not been
performed.
– ECM has been replaced and the Closed Throt-
tle and Idle Actuator reset has not been per-
formed.
Electrical Inspection
Refer to THROTTLE POSITION SENSOR (TPS)
and IDLE BYPASS VALVE in ELECTRONIC MAN-
AGEMENT below.
To verify the engine RPM with tachometer
(P/N 529 014 500), use the following proce-
dure.
The inductive tachometer works on these ignition
coils (stick coils) as well as on regular high tension
coil. Simply wrap the tachometer's wire a few
times around the protruding part of ignition coil.
A32CCIA
TYPICAL
Replacement
Removal
To remove the throttle body from engine, proceed
as follows:
– Disconnect air intake silencer from throttle
body. Move boot away.
– Remove retaining screws of throttle body.
R1503motr205A
2
2
1
4-TEC NATURALLY-ASPIRATED MODELS
1. Throttle body
2. Screws
408 smr2004-Complete Line Up