Diesel relative compression questions

[IDT7]

Hi everyone.
I've got few questions about relative compression on common rail diesel engines.
Today I have done one on 1.6 HDI 9HW Peugeot and first issue was - after the test I've connected injectors back on but engine completely lost throttle so I had to do hard reset in the end.
Second test was on Hyundai Getz 1.5 I could not start the engine after the test and had to replace camshaft sensor.
What happens with injector voltage when disconnected
How do you guys safely disable diesel injection for relative compression tests?

[greasybob]

Jump the starter relay/solenoid with the key off. If a manual tranny make sure it's not in gear.

[IDT7]

ok but what about high pressure pump control,what is going to happen with presure generated?when ecu is not controlling anything,worried about overpressurising system

[Joe Rappa]

That vehicle is not available in the US, so I can't look it up. Do you have access to service info on that car? I'm not sure I'd try messing with a CRD without following the correct service procedure. It has to be available someplace.

Joe