Hyundai Sonata 1991 Shop Manual page 255

MPI SYSTEM
4. Turn the ignition switch to ON (do not start the engine) and
leave it in that position for 15 seconds or longer; then check
to be sure that the idle speed control servo is fully retracted
to the curb idle position.
NOTE
When the ignition switch is turned to ON, the ISC plunger
extends to the fast idle position opening; then, after 15
seconds, it retracts to the fully close (curb idle) position.
Motor position sensor : 0.9V
31V266
Fixed SAS
ISC
adjusting~~~;":';
screw
Curb idle rpm 750
±
100 rpm
10. If the engine speed is not as specified, adjust the ISC
adjusting screw to obtain the standard rpm.
11. Tighten the fixed SAS until the engine speed starts to
increase. Then, loosen it until the engine speed ceases to
drop (touch point) and then loosen a half turn from the touch
point.
12. Stop the engine.
5. Turn the ignition switch OFF.
6. Disconnect the ISC motor connector and secure the ISC
motor at the fully retracted position.
7. In order to prevent the throttle valve from sticking, open it
two or three times; then release it to let it click shut. and
sufficiently loosen the fixed SAS.
a.
Start the engine and let it run at idle speed.
9. Check that the engine rpms are within the standard value.
If the multi-use tester is used, press code No. 22 and read
engine rpms.
31-30