ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-67
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Is there DTC(s) other than fuel system
(DTC P0171 / P0172)?Go to applicable
DTC Diag. Flow
Table.Go to Step 3.
3Check HO2S-1 Output Voltage.
1) Connect scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and keep
it at 2000 r / min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator pedal
5 to 6 times continuously and take foot off from pedal to
enrich and enlean A / F mixture). See Fig. 1.
Does HO2S-1 output voltage deflect between below 0.3 V and
over 0.6 V repeatedly?Go to Step 4.Go to DTC
P0130 Diag.
Flow Table
(HO2S-1 circuit
check).
4Check Fuel Pressure (Refer to section 6E2 for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge.
3) Check fuel pressure. See Fig. 2.
With fuel pump operating
and engine at stop : 270 – 310 kPa, 2.7 – 3.1 kg / cm
2,
38.4 – 44.0 psi.
At specified idle speed : 200 – 240 kPa, 2.0 – 2.4 kg / cm
2,
28.4 – 34.1 psi.
Is measured value as specified?
Go to Step 5.Go to Diag. Flow
Table B-3 Fuel
Pressure Check.
5Check Fuel Injectors and Circuit.
1) Using sound scope (1) or such, check operating sound of
each injector (2) when engine is running. Cycle of operating
sound should vary according to engine speed. See Fig. 3.
If no sound or an unusual sound is heard, check injector
circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel injector
connector.
3) Check for proper connection to fuel injector at each terminal.
See Fig. 4.Go to Step 6.Check injector
circuit or replace
fuel injector(s).
4) If OK, then check injector resistance.
Injector Resistance: 12 – 13 ohm at 20C (68F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume referring to
Section 6E2. See Fig. 5.
Injected Fuel Volume: 38 – 48 cc / 15 sec 1.28 /
1.34 – 1.62 / 1.69 US / Imp.oz / 15 sec)
7) Check each injector for fuel leakage after injector closed.
Fuel Leakage: Less than 1 drop / min.
Is check result in step 1) and 3) to 7) satisfactory?
6Check EVAP Canister Purge Valve.
1) Disconnect purge hose (1) from EVAP canister.
2) Place finger against the end of disconnected hose.
3) Check that vacuum is not felt there when engine is cool and
running at idle. See Fig. 6.
Is vacuum felt?Check EVAP
control system
(See Section
6E2).Go to Step 7.
7Check intake manifold absolute pressure sensor for
performance (See DTC P0105 Diag. Flow Table).
Is it in good condition?Go to Step 8.Repair or
replace.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-69
Ignition coil assembly
for No.1 & No.4 spark plugs
Ignition coil assembly
for No.2 & No.3 spark plugs
Ignition switch
Main relay
Main
fuseRelay box
To ignition switch
CKP sensorCMP sensorNo.1 injector
No.2 injector
No.3 injector
No.4 injector Fuse box
DTC P0300 RANDOM MISFIRE DETECTED (Misfire detected at 2 or more
cylinders)
DTC P0301 CYLINDER 1 MISFIRE DETECTED
DTC P0302 CYLINDER 2 MISFIRE DETECTED
DTC P0303 CYLINDER 3 MISFIRE DETECTED
DTC P0304 CYLINDER 4 MISFIRE DETECTED
CIRCUIT DESCRIPTION
ECM (PCM) monitors crankshaft revolution speed and engine speed via the crankshaft position sensor and cylin-
der No. via the camshaft position sensor. Then it calculates the change in the crankshaft revolution speed and from
how many times such change occurred in every 200 or 1000 engine revolutions, it detects occurrence of misfire.
When ECM (PCM) detects a misfire (misfire rate per 200 revolutions) which can cause overheat and damage to
the three way catalytic converter, it makes the malfunction indicator lamp (MIL) flash as long as misfire occurs at
that rate.
After that, however, when the misfire rate drops, MIL remains ON until it has been judged as normal 3 times under
the same driving conditions.
Also, when ECM (PCM) detects a misfire (misfire rate per 1000 revolutions) which will not cause damage to three
way catalytic converter but can cause exhaust emission to be deteriorated, it makes MIL light according to the 2
driving cycle detection logic.
Below
specified value
6-1-70 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
1. CKP sensor signal
2. No.1 fuel injector signal
3. No.3 fuel injector signal
4. Fuel injection time
Display of fuel injection signal using oscilloscope
Waveforms at specified idle speed5ms/Div
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Engine under other than high revolution condition
Not on rough road
Engine speed changing rate
Manifold absolute
pressure changing rate
Throttle opening changing rate
Misfire rate per 200 or 1000 engine revolutions (how
much and how often crankshaft revolution speed
changes) is higher than specified valueEngine overheating
Vacuum leaks (air inhaling) from air intake system
Ignition system malfunction (spark plug(s), high-
tension cord(s), ignition coil assembly)
Fuel pressure out of specification
Fuel injector malfunction (clogged or leakage)
Engine compression out of specification
Valve lash (clearance) out of specification
Manifold absolute pressure sensor malfunction
Engine coolant temp. sensor malfunction
PCV valve malfunction
EVAP control system malfunction
EGR system malfunction
DTC CONFIRMATION PROCEDURE
NOTE:
Among different types of random misfire, if misfire occurs at cylinders 1 and 4 or cylinders 3 and 2 simulta-
neously, it may not possible to reconfirm DTC by using the following DTC confirmation procedure. When
diagnosing the trouble of DTC P0300 (Random misfire detected) of the engine which is apparently misfir-
ing, even if DTC P0300 cannot be reconfirmed by using the following DTC confirmation procedure, pro-
ceed to the following Diag. Flow Table.
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester.
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for:
–Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Intake air temp.: between –10C and 80C (14F and 176F)
–Engine coolant temp.: –10C, 14F or higher
4) Start engine and keep it at idle for 2 min. or more.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
6) If DTC is not detected at idle, consult usual driving based on information obtained in “Customer complaint analy-
sis” and “Freeze frame data check”.
Reference
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-71
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE“.
2Is there DTC other than Fuel system (DTC P0171 / P0172)
and misfire (DTC P0300-P0304)?Go to applicable
DTC Diag.
Flow Table.Go to Step 3.
3Check Ignition System.
1) Remove spark plugs and check them for;
Air gap: 1.0 – 1.1 mm (0.040 – 0.043 in.) See Fig. 1.
Carbon deposits
Insulator damage
Plug type
If abnormality is found, adjust, clean or replace.
2) Disconnect all injector connectors. See Fig. 2.
3) Connect spark plugs to high tension cords and then ground
spark plugs.
4) Crank engine and check that each spark plug sparks.
Are above check results satisfactory?Go to Step 4.Check ignition
system parts
(Refer to Section
6F1).
4Check Fuel Pressure (Refer to Section 6E2 for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig. 3.
3) Check fuel pressure.
With fuel pump operating
and engine at stop : 270 – 310 kPa, 2.7 – 3.1 kg / cm
2,
38.4 – 44.0 psi.
At specified idle speed : 200 – 240 kPa, 2.0 – 2.4 kg / cm
2,
28.4 – 34.1 psi.
Is measured value as specified?
Go to Step 5.Go to Diag. Flow
Table B-3 fuel
pressure check.
5Check Fuel Injectors and Circuit.
1) Using sound scope (1) or such, check operating sound of
each injector (2) when engine is running. Cycle of
operating sound should very according to engine speed.
See Fig 4.
If no sound or an unusual sound is heard, check injector
circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel injector
connector.
3) Check for proper connection to fuel injector at each
terminal. See Fig. 5.
4) If OK, then check injector resistance.
Injector Resistance: 12 – 13 ohm at 20C (68F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume referring to
Section 6E2. See Fig. 6.
Injected Fuel Volume: 38 – 48 cc / 15 sec (1.28 / 1.34 –
1.62 / 1.69 US / Imp. oz / 15 sec)
7) Check each injector for fuel leakage after injector closed.
Fuel Leakage: Less than 1 drop / min.
Is check result in step 1) and 3) to 7) satisfactory?Go to Step 6.Check injector
circuit or replace
fuel injector(s).
6-1-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Disconnect connectors when checking plugs
for spark1. Fuel delivery pipe
2. Fuel feed hose
3. FUel pressure
gauge & 3 way joint
STEPACTIONYESNO
6Check PCV valve for clogging (See Section 6E2).
Is it in good condition?Go to Step 7.Replace PCV valve.
7Check EVAP Canister Purge Valve for Closing.
1) Disconnect purge hose (1) from EVAP canister.
2) Place finger against the end of disconnected hose.
3) Check that vacuum is not felt there, when engine is
cool and running at idle. See Fig. 7.
Is vacuum felt?Check EVAP
control system
(See Section 6E2).Go to Step 8.
8Check intake manifold pressure sensor for performance
(See DTC P0105 Diag. Flow Table).
Is it in good condition?Go to Step 9.Repair or replace.
9Check engine coolant temp. sensor for performance
(See Section 6E2).
Is it in good condition?Go to Step 10.Replace engine
coolant temp.
sensor.
10Check parts or system which can cause engine rough
idle or poor performance.
–Engine compression (See Section 6A1).
–Valve lash (See Section 6A1).
–Valve timing (Timing belt installation. See Section 6A1).
Are they in good condition?Check wire harness
and connection of
ECM (PCM) ground,
ignition system and
fuel injector for
intermittent open
and short.Repair or replace.
Fig. 1 for Step 3 Fig. 2 for Step 3 Fig. 3 for Step 4
Fig. 4 for Step 5 Fig. 5 for Step 4 Fig. 6 for Step 5
Fig. 7 for Step 7
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.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-101
1. Fuel injector
2. Delivery pipe
3. Fuel regulator
4. Fuel filter
5. Fuel pump
Special Tool
(A) Gauge (09912-58441)
(B) Hose (09912-58431)
(C) 3-way joint (09912-58490)
TABLE B-3 FUEL PRESSURE CHECK
INSPECTION
STEPACTIONYESON
11) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge.
3) Check fuel pressure by repeating ignition switch
ON and OFF.
Is fuel pressure then 270 – 310 kPa
(2.7 – 3.1 kg / cm
2, 38.4 – 44.0 psi)?
Go to Step 2.Go to Step 5.
2Is 200 kPa (2.0 kg / cm2, 28.4 psi) or higher fuel
pressure retained for 1 minute after fuel pump is
stopped at step 1?Go to Step 3.Go to Step 4.
31) Start engine and warm it up to normal operating
temperature.
2) Keep it running at specified idle speed.
Is fuel pressure then within 200 – 240 kPa
(2.0 – 2.4 kg / cm
2, 28.4 – 34.1 psi)?
Normal fuel pressure.Clogged vacuum
passage for fuel
pressure regulator or
faulty fuel pressure
regulator.
4Is there fuel leakage from fuel feed line hose, pipe or
their joint?Fuel leakage from
hose, pipe or joint.Go to Step 10.
5Was fuel pressure higher than spec. in step 1?Go to Step 6.Go to Step 7.
61) Disconnect fuel return hose from fuel pressure
regulator and connect new return hose to it.
2) Put the other end of new return hose into approved
gasoline container.
3) Operate fuel pump.
Is specified fuel pressure obtained then?Restricted fuel return
hose or pipe.Faulty fuel pressure
regulator.
6-1-102 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
1. Fuel delivery pipe
2. Fuel feed hose
3. Fuel return hose
Special Tool
(A) Gauge
(B) Hose
(C) 3-way joint
STEPACTIONYESON
7Was no fuel pressure applied in step 1?Go to Step 8.Go to Step 9.
8With fuel pump operated and fuel return hose blocked
by pinching it, is fuel pressure applied?Faulty fuel pressure
regulator.Shortage of fuel or fuel
pump or its circuit
malfunction.
91) Operate fuel pump.
2) With fuel return hose blocked by pinching it, check
fuel pressure.
Is it 450 kPa (4.5 kg / cm
2, 63.9 psi) or more?
Faulty fuel pressure
regulator.Clogged fuel filter,
restricted fuel feed
hose or pipe, Faulty
fuel pump or fuel
leakage from hose
connection in fuel
tank.
101) Disconnect fuel return hose from pressure
regulator and connect new return hose to it.
2) Insert the other end of new return hose into
approved gasoline container.
3) Check again if specified pressure is obtained.
While doing so, does fuel come out of return hose?Faulty fuel pressure
regulator.Fuel leakage from
injector, Fuel leakage
from between injector
and delivery pipe,
Faulty fuel pump
(faulty check valve in
fuel pump) or Fuel
leakage from fuel
pressure regulator
diaphragm.
Fig. for STEP 1