Dad’s old 93 been sitting for 8 years.

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Erik the Awful

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Or "More Power, arg arg arg" (don't know how to spell the grunt), LOL
I do have to admit that when I replaced my TBI's fuel pump I went for the more powerful Vortec pump.

If the fuel's varnished up, change the pump and sock. Mine was a non-functional, gooey mess.
 

Aarong23

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I'd be inclined to do a new fuel pump, too. Drop the tank. Lift/tilt the box. Either/Or.
The ones in these trucks have a shady rep to begin with.
...& they always F-up at the worst possible moment.
Like doing 75 in the fast lane of five, on the uphill side of a major bridge, during rush hour. Engine coughed, and...
Dead. Nothin'. Out cold.
(Tim 'the Tool Man' Taylor voice.) "OhhhNoooo."
Now I keep a spare in the parts stash.
That has happened to me twice. In two different 400s. One at a now extinct video rental place. Lol the other driving down the road. Thankfully the ol, bang on the tank with a hammer trick got me home.
 

PlayingWithTBI

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You're pushing 60psi to a TBI?
I'm using a Vortec pump too and was running @28PSI but couldn't get it to idle so, I went down to 20PSI and now as high as 94 in my VE tables at 85+ MAP. The Vortec pump gives you more flow (155L/Hr IIRC) the TBI pump won't give you enough fuel for a more than stock engine.
 

haroldwca

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Hey, BFrazier, welcome. I'm new here myself, but not to the old Chevy truck world. In fact, I did just what you're talking about doing. Mine is an '88 SWB 4WD 5.7 L standard cab that sat still for 10 years until I bought it. I shot about 1/2 a can of penetrating oil into the cylinders and let it sit for a week before I tried to turn it by hand. It turned, so I attempted to start it. No luck. I dropped the tank. The inside looked like the Titanic looks now, so I threw it in the trash and bought a new loaded tank for about $300. Still no luck. I then took the throttle body apart and cleaned it. The old fuel had ruined the pressure regulator, so I replaced the regulator ($ not much) and cleaned the throttle body. I also ended up replacing both injectors ($40 each). The fuel system is brand new except for the gas cap and fuel gauge. I cranked it, and it ran.

You can do this. As the others have said, the fuel pump is the first place to start. You said you have a '93 model? You have an ALDL (pre-OBDII) terminal. On ALDL, Terminal G (lower left) activates the fuel pump when 12V is applied to it. CAREFULLY touch a wire from 12V to this port (and nothing else), and you should hear the fuel pump activate. If it doesn't, the pump is bad. Replace it, and the fuel filter while you're under the truck.

The following sequence assumes that you have spark from the distributor to the plugs.

Once you have either verified that you have a good pump, or replaced the bad one, (and cleaned or replaced the tank) attempt to start the engine. If it doesn't start, check the fuel injectors by unplugging the connector at the top of each injector, and touching the terminals with a 9V battery. If you hear a click, it's good. If you don't hear a click, replace the injector(s). Once the injectors are verified or replaced, give it another try. If it doesn't start, the only component left in the fuel system is the fuel pressure regulator. It is located in the back of the throttle body. A replacement kit is available. Clean the crud out of the regulator housing area of the throttle body, replace the sacrificial components, and fire it up.

Good luck and let us know how it goes !
 

PlayingWithTBI

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Some good advice - here's some more...

CAREFULLY touch a wire from 12V to this port (and nothing else), and you should hear the fuel pump activate
You should be able to hear it run for 2 seconds when you turn the key on too.

If it doesn't, the pump is bad.
You should check the fuse feeding the fuel pump relay and ground connection at the tank too before you replace the pump. How about the fuel filter? Here's a link to manuals you can use to troubleshoot...
https://www.gmt400.com/threads/88-95-service-manuals.43575/

the only component left in the fuel system is the fuel pressure regulator. It
You need to put a pressure gauge on it 1st.
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Get a scanner (not just a code reader) for OBD1 or TunerPro RT and an ALDL cable so you can see what's going on with your sensors such as, TPS, IAC, MAP, CTS, SA, BPW, etc (an example of my 88 while cruising)

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Erik the Awful

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"You need to put a pressure gauge on it 1st."

Got a link for a TBI gauge installation for less than $60? All I could find was the CFM Technologies adapter and gauge, and that's a pricey bit of kit just for checking fuel pressure.
 

PlayingWithTBI

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You have to drill a hole (offset) through the TB base and bend the MAP vacuum tube a little for the screw and thumb wheel.
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Here's what it looks like from underneath. One issue, you can't get to the adjustment screw without removing the TB from the manifold - too tight.

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