87tbi starting problems

[mfencl]

I got a 87 v20 chevy 350 tbi, I'm not getting fuel to spray out of the injectors but one which is dumping the fuel I've replaced the ecm,fuel pumpfilter and relay, injectors,injector wires new distrubtor only thing havnt replaced is coil tps maps sensor and the thing next to maps sensor any ideas on why it isn't wanting to put fuel out need help
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[gchemist]

How old is the fuel pump? I've seen plenty of TBI trucks not start due to low fuel pressure. GM did not install a test port. You have to add an adaptor for a gauge or test at the fuel filter.

[mfencl]

honestly idk I'm guessing its orginal pump but not sure but wouldn't at least both get a little fuel coming out of em?
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[gchemist]

Nope. Fuel pressure is already low at 13-15 PSI for TBI. Pour a little fuel down the throttle body. Crank it. If it runs a few seconds, you have fuel delivery problem and electrical is fine. If it runs a few seconds, I bet the fuel pump is toast. I've being seen a lot of TBI fuel pumps failing latetly. Mostly due to age and heat in Texas.

[rs72z]

I thought you had already checked the pump? The rubber hose that connects the pump to the sending unit is probably bad if you here the pump running. If you drop the tank replace the pump regardless.

[mfencl]

yeah I'm gunna replace the pump this weekend and yeah that's what I've heard to that the pumps go bad and hoses too
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[Don SC]

Here's another possibility- the oil pressure sensing system . On the tbi systems, the fuel pump wiring is tied into the oil pressure system. If the oil pressure isn't sensed, power to the fuel pumps is interrupted by the ecm, and you get no fuel to the injectors.
Btw, if you turn on the ignition, can you hear the pump run? You should be able to, if there's B+ voltage to the pumps.

[mfencl]

yeah I can hear the pump I did a light test on a red wire goin to the pump n bulb was dim
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[motornut]

i replaced the pump in my 87 only find out it wasn't the prob
I found a nic in the wire over the rear wheel well
tested and it was getting power...I thought

the power wire was nic/cut and corroded... replaced it no more probs
try a temp wire.....

[mfencl]

what ended up bein ur problem cuz I've replaced just about everything electrical besides wires and where's the oil system tie in witht the fuel
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[Don SC]

The oil pressure switch is a backup for the fuel pump relay. It's supposed to prevent a no-start if the relay goes bad. But your relay is new, so I'm re-thinking what I said about the oil pressure system being a problem. It's probably ok. Since you can hear the pump run, the voltage is being sent by the ecm.
ftp://ftp.diy-efi.org/pub/gmecm/manuals/1227747/