Page 234 of 557
6-1-78 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Ignition
switch
Main fuseRelay
boxMain
relay
EGR valve
2 C13
DTC P0400 EXHAUST GAS RECIRCULATION FLOW MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
While running at specified vehicle speed after
engine warm-up
During deceleration (engine speed high with closed
throttle position ON) in which fuel cut is involved,
difference in intake manifold absolute pressure
between when EGR valve is opened at specified
value and when it is closed is larger or smaller than
specified value.
2 driving cycle detection logic, monitoring once / 1
drivingEGR valve or its circuit
EGR passage
ECM (PCM)
Page 247 of 557
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-91
Relay box
Main fuseMain relay
IAC valveTo other valve
DTC P0505 IDLE CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
No closed signal to IAC valve is detected after
engine start.
2 driving cycle detection logic, continuous monitoring.“R/B”, “V/W” or “B” circuit open or short
IAC valve malfunction
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start engine and run it at idle for 1 min.
4) Check DTC and pending DTC.
Page 253 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-97
Fuse box Main
fuse
DOME
RADIO
“LAMP”
DTC P1510 ECM (PCM) BACK-UP POWER SUPPLY MALFUNCTION
CIRCUIT DESCRIPTION
Battery voltage is supplied so that diagnostic trouble code memory, values for engine control learned by ECM
(PCM), etc. are kept in ECM (PCM) even when the ignition switch is turned OFF.
DTC DETECTING CONDITION
POSSIBLE CAUSE
Low voltage at terminal C02-7 after starting engine.“W” circuit open
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and run it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
STEPACTIONYESNO
1Check for voltage at terminal C02-7 of ECM
(PCM)connector connected, under each
condition, ignition switch OFF and engine
running.
Is it 10 – 14 V at each condition?Poor C02-7 connection
or intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.
If wire and connections
are OK, substitute a
known- good ECM
(PCM) and recheck.“W” circuit open.
Page 254 of 557
6-1-98 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Ignition
switch
Main
fuseMain relay
Relay boxNo.1 injector
No.2 injector
No.3 injector
No.4 injector Fuse box
TABLE B-1 FUEL INJECTOR CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check Injector for Operating Sound.
Using sound scope, check each injector for operating
sound at engine cranking.
Do all 4 injector make operating sound?Fuel injector circuit is
in good condition.Go to Step 3.
3Dose none of 4 injectors make operating sound at
Step 2?Go to Step 4.Check coupler
connection and wire
harness of injector
not making operatingnot making o erating
sound and injector
itself (Refer to Section
6E2).
4Check power circuit of injectors for open and short.
Is it normal?Check all 4 injectors
for resistance
respectively.
If resistance is OK,
substitute a known-
good ECM (PCM) and
recheck.Power circuit open or
short.
Page 255 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-99
Main
fuseIgnition
switch
Main relay
Fuel pump relay Main relay
Fuel pump
CAUTION: Check to make sure that connection is
made between correct terminals. Wrong connection
can cause damage to ECM (PCM), wire harness, etc.
TABLE B-2 FUEL PUMP AND ITS CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Check Fuel Pump Control System for Operation. See Fig. 1.
Is fuel pump heard to operate for 2 sec. after ignition switch
ON?Fuel pump circuit
is in good
condition.Go to Step 3.
3Check Fuel Pump for Operation.
1) Remove fuel pump relay from relay box with ignition
switch OFF.
2) Check for proper connection to relay at each terminals.
3) If OK, using service wire, connect terminals C44-3 and
C44-4 of relay connector. See Fig. 2.
Is fuel pump heard to operate at ignition switch ON?Go to Step 4.“P”, “B” or “R/B”
circuit open or fuel
pump malfunction.
4Check Fuel Pump Relay for Operation.
1) Check resistance between each two terminals of fuel
pump relay. See Fig.3.
Between terminals “c” and “d”: Infinity
Between terminals “a” and “b”: 100 – 150 Ω
2) Check that there is continuity between terminals “c” and
“d” when battery is connected to terminals “a” and “b”. See
Fig. 3.
Is fuel pump relay in good condition?“Y/Bl” circuit open
or poor C02-19
connection.
If wire and
connection are
OK, substitute a
known-good ECM
(PCM) and
recheck.Replace fuel pump
relay.
Page 408 of 557

ENGINE AND EMISSION CONTROL SYSTEM (TBI FOR G10) 6E1-17
1. ECM
2. Instrument panel
3. Steering wheel
1. Injector wire
2. Screws
1. Stay
3) Make sure that injector wire O-ring is free from any damage and
deterioration, and apply thin coat of spindle oil or gasoline to O-
ring.
Install injector wire and tighten new wire screw to specified
torque.
Tightening Torque
(a): 3.5 N
.m (0.35 kg-m, 2.5 lb-ft)
4) Connect battery negative cable at battery.
5) With engine “OFF” and ignition switch “ON”, check for fuel leaks.
6) Install air cleaner mounting stay as shown left.
7) Install air cleaner assembly referring to Section 6A.
ELECTRONIC CONTROL SYSTEM
ENGINE CONTROL MODULE (ECM)
CAUTION:
As ECM consists of precision parts, be careful not to ex-
pose it to excessive shock.
REMOVAL
1) Disconnect battery negative cable at battery.
2) Lower fuse box after removing bolt.
3) Disconnect couplers from ECM while releasing coupler lock.
4) Remove ECM from body.
INSTALLATION
1) Install ECM to body.
2) Connect couplers to ECM securely.
3) Install fuse box and tighten its bolt.
4) Connect battery negative cable at battery.
Page 455 of 557
ENGINE AND EMISSION CONTROL SYSTEM (SFI FOR G13) 6E2-27
ELECTRONIC CONTROL SYSTEM
ENGINE CONTROL MODULE (POWERTRAIN
CONTROL MODULE) [ECM (PCM)]
CAUTION:
As ECM (PCM) consists of precision parts, be careful not to
expose it to excessive shock.
Removal
1) Disconnect battery negative cable at battery.
2) Disable air bag system, refer to “DISABLING THE AIR BAG
SYSTEM” in Section 9J if equipped.
3) Lower fuse box after removing screws and remove fuse box
bracket.
4) Remove ECM (PCM) (1) from body.
5) Disconnect couplers from ECM (PCM).
Installation
Reverse removal procedure noting the following:
Connect couplers to ECM (PCM) securely.
MANIFOLD ABSOLUTE PRESSURE SENSOR (MAP
SENSOR)
Inspection
Check MAP sensor referring to “MAP Sensor Individual Check” in
DTC P0105 Flow Table. If malfunction is found, replace.