Hyundai Sonata 1991 Shop Manual page 273

MPI SYSTEM
Check conditions
Test
Probable cause of malfunction
Check points
specification (or action)
Air temperature o Ignition switch: Air temperature
Temperature o Malfunction of air temperature or
sensor ON, or engine
°C (OF)
°C (OF)
related circuitry
o Service data running
-20 (-4)
-20 (-4)
o Item No.13
o
(32) 0(32)
20 (68) 20 (68)
40 (104)
40 (104)
80 (176)
80 (176)
o Ignition switch: Warm by using Increases
ON hair dryer or
other method.
Throttle-position
o Hold for 15 sec- Throttle valve
Voltage (mV) o Throttle-position sensor maladjust-
sensor
onds or longer
Idling position
ment
o Service data with the igni-
450-550
o Throttle-position sensor or related
o Item No.14 tion
switch
at
Opens slowly.
Becomes
circuitry malfunction
"ON".
higher in
proportion to
valve opening
Fully open
4,500-5,500
Motor position sen-
o Engine: idling Engine
Voltage (mV) o If the voltage is low, check
sor after warm-up
condition
whether or not there is air intake.
o Service data (The idle posi-
Idle (750 rpm)
500-1,300
o If the voltage is high, the probable
o Item No.15
tion switch
cause is:
must be ON.)
1) Deposits adhered to the throttle
valve
2) Increased engine resistance
o If the voltage or idling speed is
abnormal even though each part
of the engine is normal, the prob-
able cause is:
1) Improper adjustment of the idle
speed control
andlor
the throt-
tle position sensor
2) Malfunction of the motor posi-
tion sensor or the related circuit
31-48