Engine cooling symptom diagnosis

Schematic and routing diagramSpring pre-load adjustment
To change the spring pre-load,
turn the adjuster 1 clockwise or
counterclockwise. Turning the
adjuster clockwise will increase
the spring pre-load. Turning the
adjuster counterclockwise will
decrease the spring pre-load.
There are five grooved lines on
the side of the adjuster 1 for re ...
Special tools and equipment
Recommended service material
Note
required service material is also described in the following.
“Throttle body components” “engine bottom side assembly”
Special tool
...
DTC “c28” (p1655): secondary throttle
valve actuator (stva) malfunction
Detected condition and possible cause
Detected condition
Possible cause
The operation voltage does not reach the stva.
Ecm does not receive communication signal from the
stva. Stva can not operate properly or its motor locked
Stva malfunction.
...