Hi i am new to this forum and also relatively new to pre obd2 gm diagnostic techniques. I was recently given a 1990 firebird automatic trans 3.1 fuel injected v6. The car has been sitting for almost 10 years! After some preparation yesterday i attempted to start the car but it will only turn over. It will start very briefly on starting fluid. I also cant hear the pump prime. The reason i suspect a possible ground issue is as follows, when the key is turned to the on position the fan comes on the oil pressure and fuel gauge read beyond 100% (the gas tank has maybe 2 gal in it) and the temp gauge reads partially warmed up. Also the check engine light flashes on for a fraction of a second rather than turning on and then off normally. The previous owner tells me that before it was parked it had an intermittent stalling issue. And the car sat with the ecm unplugged for about a year
Since i got the car ive only replaced the fuel injectors, spark plugs and wires, distributer cap and rotor, most of the vac lines, the plenum gasket and done an oil change
Any insight would be greatly appreciated! Thanks in advance

 

It sounds like the fuel pump might have given up, and after ten years, the gas is guaranteed to be bad.

 

The thought def crossed my mind, any idea wich of the three wites is the hot wire? I want to see if its sending power

 

If you're referring to the fuel sending unit, the gray wire is the fuel pump, the black is ground, and the (purple?) other one is for the float sender.

The ground for the sender is under the driver's side lower rear seat. Generally, the fuel gauge has nothing to do with the oil gauge other than the power circuit. The pressure sender by the oil filter is probably either dead or somehow disconnected (broken/chewed wire).