MPI <4G1> -
Troubleshooting
13A-73
Standard wave pattern
Crank angle
sensor output
wave pattern
(V)
75
_
BTDC
2 engine revolutions
(1 camshaft revolution)
5
_
BTDC
The time (cycle time) T is
reduced when the engine
speed increases
0
Camshaft posi-
tion sensor out-
put wave pat-
tern
TDC: Top dead centre
130
°
50
°
No. 1 TDC
No. 3 TDC
No. 4 TDC
No. 2 TDC
Time
0
145
°
35
°
Wave Pattern Observation Points
Check that cycle time T becomes shorter when the engine speed increases.
Examples of Abnormal Wave Patterns
D
Example 1
Cause of problem
Sensor interface malfunction
Wave pattern characteristics
Rectangular wave pattern is output even when the engine
is not started.
D
Example 2
Cause of problem
Loose timing belt
Abnormality in sensor disk
Wave pattern characteristics
Wave pattern is displaced to the left or right.