fuel delivery....
 

I have a 78 chevy stepside..with a 1989 tuned port fuel injected iroc z28/corvette engine it wont start...parked it 2 months ago and next morning would not start..changed fuel pump..filters..stiill wont start..there is no fuel delivery to injectors...pump is at 45psi..gets fuel at rail..when gas is thrown down the intake it starts for a moment..checked all relays and fuses everything is good....now one day the fuel pump will be shooting out gas and the next day it doesnt do anything but a drip and there is gas in both tanks..more so in one tank ..but it seems like its out of gas...had a scanner plugged in to port and it came up that computer was bad..got a new one..but still truck wont start...now my mechanic and myself are about to pull gas tanks to see if something is wrong in the tanks...this seems extreme..but dont know what else to do...thinking also the anti theft tripped..but the key i have has no chip...wires check out ok too...everything ran perfectly when i shut her off 2 months ago....im not sure what to do at this point...anyone had similar problem and some help would be appreciated here........thanx,....
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Re: fuel delivery...
 

You can disable the PATS (passive anti-theft system) in the tune with a simple checkbox (or pay someone to have it done if you don't tune yourself). If you were bypassing it externally before, that wire or resistor may have came loose causing the fuel pumps to only run for a few seconds during the initial key-on prime phase. That's almost for sure what's going on.

Re: fuel delivery....
 

If you have 45psi at the rail it's probably not the fuel pump..It sounds like a Vats problem. If you have the 89 programing you have to have the vats removed. When you got the new computer did you remove your prom and replace it in the new computer? Try the Thirdgen.org website..Tons of TPI info on ther.

Re: fuel delivery....
 

Yes i replaced it
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Re: fuel delivery...
 

I agree...Maybe a noid light to see if there is injector pulse..

Re: fuel delivery....