Posted on 5/1/2024
![How to perform a relative compression test (lab scope setting and graph settings)](https://17thstreetauto.com/Files/EmailCampaigns/18192532_10211409720910712_1519730865138195706_o.jpg)
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)