How to perform a relative compression test (lab scope setting and graph settings)

Relative compression test: 

1. Battery charged 

2. Disable fuel system (WOT on certain vehicles) 

3. Lab scope 

4. Low amps probe 60A on either pos/neg batt cable (zero calibrate) 

5. Voltage setting at 500mV (10mV/1A) 

6. 2.0 sec scale 

7. RPM clamp at number 1 to identify which cylinder (if massive compression drop is detected) find firing order 

8. Pressure transducer to find out which mechanical part ie. Int/exh valve etc. (next post) 

Tags:relative compression test procedures