Operation CHARM
: Car repair manuals for everyone.
Home
>>
Dodge or Ram Truck
>>
1993
>>
D 150 Pickup V6-239 3.9L
>>
Repair and Diagnosis
>>
Engine, Cooling and Exhaust
>>
Engine
>>
Compression Check
>>
Service Precautions
Compression Check: Service Precautions
COMPRESSION TESTING
When performing a compression test, remove the fuel pump relay fuse and disconnect power to the ignition. This will stop fuel flow to the injectors and prevent engine from starting.