Hello, I own a 2000 V6 Camaro That is having some issues and I was wondering if anyone can help me.

Just two days ago I had the fuel pump replaced after it went out on me, and It has been running smoother than it has before. Tonight however I tried to crank it, It started up like normal then suddenly the oil pressure gauge drops and check gauge light is on. check engine light has been on because of a bad oxygen sensor.But Now wont turn over or start and gauge is still on.
The oil was slightly low when I checked it, over 6 times. It has part synthetic high mileage oil in it and it did need to be changed to a thicker oil.

Can anyone please tell me what it could be and how to fix it.

 

is it clicking when you try to start it?

 

As Craby suggests - is there a click?
No heavy click, as in starter solenoid not engaging, not enough power to starter - clean battery clamps and posts.
Battery cables and their clamps in good shape?
if questionable, replace cable assembly with min 1 GA cable - no screw-on clamps.

Other choice is swap starter relay in relay box on drvr side of engine compartment with same part number.