96 240sx wiring running problem

[obeeone]

Looking for some advice from the wiring guru's. I have been working on a friends car trying to diagnose a running condition on the car. Idled very poorly and had no power now will not start at all.
Digging into the diagnostics in the FSM I started checking proper voltages and resistances in the major sensors etc.
What I found was that the ECCS relay that powers the MAF, Cam Position Sensor, and Evap Canister Purge Volume Control Valve has a black wire with white stripe. This wire should supply battery voltage to the sensors and I was only getting a max of 4.9 volts at the MAF and Cam sensor with the Evap plugged in then with the Evap unplugged my voltage would go to 7.0.
I also had a question about the resistance between the signal wire and the ground wire from the MAF. I have no resistance or OL on my multimeter with the ecu unplugged then about 42 ohms with the ecu plugged in. Anyone know as I cannot find any specification on this?
At this point I am assuming I have a short somewhere in the wiring harness and will start unraveling things to find out, but wanted to get some advice or perspective as this is my friends only source of transport right now.
Thanks all.