E TEXTBOOK MPI M2 MPI

5. ON-VEHICLE INSPECTION AND SERVICE


<Engine-ECU Monitoring Items>
This monitor item includes many useful items for understanding the engine conditions con-
trolled by the Engine-ECU.
However, it is hard to show the definite specification of each item, since its value may vary
to a large extent with a little difference in the measuring conditions, environment, and
changes with the lapse of time, etc. on the objective vehicle. Therefore, this document will
describe only the check conditions, display range, and behavior of numeric values.
Display range,
Item INSPECTION ITEM M.U.T.-III display descriptions Standards at and numeric
No. each check
value
14 Throttle position The following shows learning Ignition switch: ON 500 - 2,000 mV
sensor (main) mid values of throttle valve opening
opening learning angle at idling.
value
26 Long-term fuel trim Indicates the long-term air-fuel Ignition switch: ON -10 to 10 %
ratio feedback amount.

The negative side shows a re-
duction in the injection amount,
while the positive side shows an
increase.
28 Short-term fuel trim Indicates the short-term air-fuel Engine: After -25 to 25 %
ratio feedback amount. warm-up, 2,500 r/
min without any
The negative side shows a re- load (under the air-
duction in the injection amount, fuel ratio feedback
while the positive side shows an control)
increase.
32 Detonation retard Indicates the ignition timing retar- Engine: Excessive Retards depend-
dation angle that is controlled by acceleration after ing on the de-
the detonation sensor output. warm-up gree (angle) of
acceleration
33 Detonation control Indicates the learning value to Ignition switch: ON 0 - 100 %
learned value compensate for the ignition tim-
ing that is controlled by the deto-
nation sensor output.
0 %side is retardation, and 100
% side is advance.
47 Fan motor duty Indicates the duty ratio for the Engine: After 0 - 100 %
electric cooling fan. warm-up
A/C switch: ON
(when the com-
pressor is ac-
tive)
49 Purge control sole- Indicates the duty ratio for the Engine: After 0 - 100 %
noid valve duty purge control solenoid valve. warm-up (when 4
minute has
elapsed)
58 Throttle valve con- Indicates the target opening an- Engine: After 0 - 100 %
trol servo gle of throttle valve. warm-up

(Be continued to following page)





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5. ON-VEHICLE INSPECTION AND SERVICE


Display range,
Item Standards at and numeric
No. INSPECTION ITEM M.U.T.-III display descriptions each check
value
59 Throttle valve con- Indicates the target opening an- Engine: After 0 - 5.0 V
trol servo target gle of throttle valve. warm-up
value
68 Idle speed control Indicates the learning value to Ignition switch: ON -1 to 4 L/s
learned value (A/C compensate for the opening an-
OFF) gle of idling speed control
(opening angle of throttle valve).
The negative side shows "close"
side, while the positive side
shows "open" side.
69 Idle speed control Indicates the learning value to Ignition switch: ON -1 to 4 L/s
learned value (A/C compensate for the opening an-
ON) gle of idling speed control
(opening angle of throttle valve)
with the air conditioner turned
ON.
The negative side shows "close"
side, while the positive side
shows "open" side.

72 Absolute load value Indicates the size of engine load. Engine: After 0 - 100 %
warm-up
73 Calculated load Indicates the size of engine load. Engine: After 0 - 160 %
value warm-up
BA Exhaust gas recir- Indicates the target opening an- Engine: After 0 - 100%
culation servo gle of exhaust gas recirculation warm-up
(target) <Vehicles servo.
for Hong Kong>
105 Fuel system status Indicates the air-fuel ratio feed- Engine: After Varies depend-
back control conditions. warm-up ing on the drive
OL: Open loop* 1 conditions
CL: Closed loop* 2
OL-DRV: Condition of open
loop due to acceleration and
deceleration driving
OL-SYS: Condition of open
loop due to system failure.
CL-HO2: Condition of closed
loop only using front oxygen
sensor when rear oxygen sen-
sor is failed.


*1 : Condition in which fuel is controlled without oxygen sensor signals being fed
Note
back to the engine-ECU because the condition to shift to the closed loop is not met.

*2 : Condition in which oxygen sensor signals are fed back to the engine-ECU for
Note
controlling fuel.






MMMTC VER1 5 - 20

5. ON-VEHICLE INSPECTION AND SERVICE


9. ACTUATOR TEST REFERENCE TABLE (For CY4A with 4B1MPI Engine)

Item Inspection Item Drive content Inspection condition Normal condition
No.
1 Injector Cut off No. 1 injector Engine: After warm-up, Engine is changed
idle operation (Cut off (becomes unstable or
Cut off No. 2 injector injectors sequentially to stalled)
check for a cylinder that
Cut off No. 3 injector
does not change engine
Cut off No. 4 injector in idle status)

9 Fuel pump Drive fuel pump to circulate Ignition switch: ON Operating noise audi-
fuel ble
Check for pump oper-
ating noise near fuel
tank
10 Purge control Switch solenoid valve from Ignition switch: ON When the valve is ac-
solenoid valve OFF to ON tuated, operating noise
is audible
14 Cooling fan mo- Actuate the fan motor Ignition switch: ON Fan motor rotates at
tor high speed
16 A/C compressor Switch the A/C compressor Ignition switch: ON The operating sound
relay relay from OFF to ON of A/C compressor is
audible
17 Inlet oil feeder Switch the inlet oil feeder Ignition switch: ON When the valve is ac-
control valve, control valve and exhaust tuated, operating noise
exhaust oil feed- oil feeder control valve from is audible
er control valve OFF to ON












































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