Chevrolet 1977 light duty truck, Service Manual

Page: 615 / 861

HIGH ENERGY IGNITION SYSTEM V8 engine
PROBLEM: engine RUNS ROUGH or CUTS OUT
’
STEP
SEQUENCE
RESULT
C H EC K S P A R K
PL U G S & PLU G W IR E S
® - ---------------------- j -------------
_
/T-N -------------------
( S o - ----------- 0 > - - i R U N S SMOOTH
^ 4 ^ - r
R E P A IR OR
R E P L A C E
RU N S ROUGH
r — 0 . —
@
O
D ISC O N N EC T
3 W IR E C O N N ECTO R
I
V IS U A L L Y IN SPEC T R E P A IR AS U
FO R M O IST U R E, DUST, N E C E S S A R Y
C R A C KS, BU R N S, ETC.
R U N S S M O O T H
- - 0 — ■- j
RUN S ROUGH
EITH ER TEST
READS 6 000
(J)
TO 30,000 OHMS
C O N N E C T
O H M M E T E R
C ^ > — - 0 K
BOTH TESTS
REA D IN F IN IT Y
R E P L A C E
CO IL
R E M O V E G R E E N & W H IT E
L E A D S FR O M M O DU LE
RU N S SMOOTH
LESS
TH A N IN F IN IT Y
(X 1000 S C A L E )
R E P L A C E CO IL
(PICK UP)
RU N S ROUGH
f
CONNECT
O H M M ET ER FRO M
G RO U N D TO E IT H E R
LEA D
R E A D S IN F IN IT E
(X 1000 S C A L E )
R E P E A T ST EPS 4 AND
5
W H IL E M O VING VAC.
A D V A N C E W ITH SC R EW
D R IV E R . IF R E A D IN G
IS S T IL L OK
CONNECT O H M M ET ER
A C R O SS 2 LE A D S
R EA D S 500 TO
1500 OHMS
R U N S SMOOTH
DOES NOT R EA D
500 TO 1500 OHMS
R E P L A C E C O IL
(P IC K U P )
R U N S ROUGH
R E P E A T ST E PS
1 T H R U 5
C H E C K M O D U L E
W I T H T E S T E R
R E M O V E A N D
R E P L A C E M O D U L E