Impedance measurement on power lines

We are using precision Multimeters in resistance mode and set them at manual 10K range for checking impedances on all power lines (versus ground) of our products.
We established Ohm ranges for each power line of a product in order to know if the circuit looks ok before applying power.

We have some products that have very sensible parts such as DDR3 memories with 0.75V±0.0375V powers and Altera FPGA with 0.9V±0.03V.

By using another multimeter, we measure around 9V between the unconnected probes of different manufacturers precision multimeters set in such 10K range resistance mode.

Even if the current is extremely small, we are worried that our sensible parts could be affected by this 9V “glitch”.

What does Altera recommend for such measurement ?

We are currently using alternative method like putting a Shunt resistor of 1K between the probes in order to keep the voltage near 0V. Of course all our range are now within 0 to 1K Ohm range and when our probes are unconnected, we always get 1.000K displayed. We can manage working with these low ranges.

thanks