Hello everyone I have a 1993 chevy half-ton, it had a 350 in it wil 160k so I built a 1994 chevy 350 in the garage, had it bored .30 over with a small cam and flat top pistons. Had the heads re-done and I put it all back together with all new parts, it still has the factory throtle body on it, The other day it was cold out 29 degrees and I started the truck up at work let it run about 5-10 minutes hopped in and drove 1 mile to a stop sign and I have 0 oil preasure so I shut the truck off and everyone told me the oil pump took it out and it's fine, changed oil filter and oil and the oil sending unit, still no oil preasure. When I start the truck it runs fine. No knocking or anything. I'm lost please help

 

eliminated the possibility of having a bad oil pressure gauge? remove the oil pressure sender and use a mechanical gauge. It`ll tell the truth.