Engine Trouble In General - Subaru XT 1988 Service Manual

2-3
TROUBLESHOOTING
Engine Trouble in General
Symbols shown in the chart refer to
the possibility of reason for the trouble
in order ("Very often" to "Rarely")
© - Very often
o -
Sometimes
t, -
Rarely
%
TROUBLE No.
1 2 3 4 5 6
7
8 9 10 11 12 13
0
t,
t,
0
t,
©
©
0
© © © © © © © © © ©
©
0 0 0
© © © © © © ©
©
0 © 0 0 0
t,
t,
0
t,
© 0 0
© 0
0
t,
0 0
0
t, t, t,
0 0
t,
0
t,
0
0
0 0 0
©
0 0 0
©
0 © 6 0 0
1
2
3 4 5 6 7 8 9 10 11 12 13
ENGINE
No.
TROUBLE
1 Starter does not turn.
r---
2
Engine will not
Initial combustion does not occur.
r----
3
start.
Initial combustion occurs.
r----
4 Engine stalls after initial combustion.
S Rough idle and engine stall.
6 Low output, hesitation and poor acceleration.
7
Surging.
8 Engine does not return to idle.
I
9 Dieseling (Run-on).
10 Afterburning in exhaust system.
11 Knocking.
12
Excessive engine oil consumption.
13
Excessive fuel consumption.
POSSIBLE CAUSE
STARTER
•
Defective battery-to-starter harness.
•
Defective starter switch.
•
Defective inhibitor switch.
•
Defective starter.
BATTERY
•
Poor terminal connection.
•
Run-down battery.
•
Defective charging system.
MPFI SYSTEM (See Chap. 2-7.)
IGNITION SYSTEM
•
Incorrect ignition timing.
•
Disconnection of spark plug cord.
•
Defective distributor.
•
Defective ignition coil.
•
Defective cord or wiring.
•
Leakage of spark plug cord.
•
Defective spark plug.
•
Incorrect cam timing.
48