Idle Air Control Functional Test
(2
of 2)
•
•
START ENGINE, ALLOW IDLE TO STABILIZE, AND RECORD ENGINE RPM.
PLACE ENGINE IN BASE TIMING OR SERVICE MODE.. DOES A
1A
NOTICEABLE DROP IN RPM OCCUR OR DOES ENGINE DIE? SEE NOTE.
YES
NOTE IN STEP 1A:
A 502/BLACKHAWK MAY NOT
DIE, BUT IDLE WILL DROP
DRASTICALLY.
EXIT SERVICE MODE AND
1B
RESTART ENGINE. ENGINE SPEED SHOULD
GRADUALLY RETURN WITHIN 75 RPM OF
RECORDED RPM WITHIN 30 SECONDS.
DOES IT?
YES
NO
IAC CIRCUIT FUNCTIONING PROPERLY.
•
•
IGNITION “OFF” FOR 10 SECONDS.
UNPLUG IAC CONNECTOR
2
IF CONNECTED.
•
•
RESTART ENGINE WITH A TEST LIGHT
CONNECTED TO GROUND.
PROBE EACH ONE OF THE FOUR IAC
TERMINALS, AND THE TEST LIGHT
SHOULD BLINK WHEN TOUCHED TO
ALL TERMINALS. DOES IT?
NO
YES
STICKY OR
FAULTY
IAC VALVE.
CHECK IAC CIRCUIT
THAT DID NOT BLINK FOR
OPEN OR SHORTED
FROM IAC HARNESS TO
J-2 CONNECTOR
CIRCUIT. IF OK,
REPLACE ECM.
Index
90-823224--2 796
ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY) - 5C-79
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
Could not find a copy until a search brought me here.
Excellent print.
Thank you