1997 GMC Suburban Fuel System

Hi,

Vehicle starts intermittantly. Cranks good and battery voltage ok. When it runs it runs real good. Suspected fuel pump but it was replaced 2 years 20K miles ago. Replaced fuel filter. Replaced Fuel pump relay. No change. Checked voltage at fuel pump connector. When it runs has 12V at connector, can hear the fuel pump cut in for 3sec when turn the key half way and the pump makes a normal sound. When it doesnt start I read 7.2V to 8V-at the connector-can still hear the fuel pump start for the 3 sec but fuel pump sound is not as loud.

Inspected wiring up to that connector under vehicle-checks good. Cleaned up the ground wire at the fuel pump connector. Reseated all fuses/relays under the hood.

Have not checked fuel pressure yet but I suspect the pump wont work right without the proper voltage.

Voltage at the relay all seems correct. I lifted the relay just high enough to get the meter probes in. Gets the 12v for 3 sec at the right place but when I checked at the connector the voltage was around 8v. Not sure where I'm loosing the voltage.