Is it good for the ground wire on map sensor harness to show 0 when tested?

Using a digital voltmeeter you should have slightly above zero, set your meter to read two decimal places to the right and check it with the key on. The reading will be something like 0.01 tp 0.10 (one tenth of a volt). If you get absolute zero then check the 5 volt reference circuit. vref is dark green/yellow wire, ground is black/dark green wire, Good luck Robert Grove, ASE Certified World Class Mobile Mechanic www.orangecountymobileautorepair.com www.wego2umobilemechanic.com