Fuel delivery issue

[eduardo95]

I recently rebuilt the motor in my truck, its an 1988 2.3 with the distributor ignition. The issue comes when i try to start the truck, there is no fuel being delivered to the injectors therefor the injectors are not injecting any fuel. There are two wires from the engine harness that are not hooked up to anything and one carries 12 volts when the ignition is on and the other wire has a lower voltage.

These wires are located near the fuel rail, one of them is solid red in color and the other wire is red with a white stripe. My guess is that these need to be connected to something that tells the injectors how much fuel needs to be delivered into the engine.

If anybody knows where these wires need to be connected please let me know. It is the one thing stopping me from firing the truck. Thanks in advance.

 

[eduardo95]

Y'all might want to open the pic in a different tab to get the original size.

 

[adsm08]

Pic no workie.

 

[eduardo95]

Pic is working now.

 

[adsm08]

Those are for the coolant temp and oil pressure sensors.

Go back through the harness and look around. See if you missed any plugs.

 

[eduardo95]

Everything else is connected but two other wire which are these..

Both come out from the cabin. Everything else that is from the engine harness is connected. Engine turns over and has good compression. Can't seem to get the fuel into it to get it running.


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[RonD]

Use a 12v test light or meter, turn key on and test any injectors wire for 12 volts.
All injectors get 12 volts with key on, they are opened by the computer using a Ground, so if there is 12 volts then injector wires are most likely OK.
The 12 v for the injectors comes from the EEC relay on the Power Box under the hood, If no 12v then check that relay, it should "click" when key is turned on.

When you first turn the key on but before starting you should hear the fuel pump come on for 1 to 2 seconds.

If that doesn't happen then there are a couple of things to check.
Under the Glove box or in the passenger kick panel is the inertia switch, this switch shuts off the fuel pump in case of an accident(sudden stop), it has a reset button on it.
Hook up a test light or 12 v meter to it's Dark green/yellow wire and a ground, turn on the key, the test light should come on for 1 to 2 seconds then go off.

The one of the wires in last picture could be the fuel pump power, it would have two wires spliced, one goes to the computer the other to the inertia switch, Green, it would plug into the bottom of the fuel pump relay.

If not then Fuel Pump Relay is not sending power
If it does come on hook up test light to the wire on the other side of the inertia switch and repeat test.

If no light then replace inertia switch or press reset a few times, and retest

Fuel pump relay should be in the Power Box under the hood, check if it is "clicking" when key is turned on

 

[eduardo95]

The fuel pump kicks on, fuel pump relay is brand new. There is 12v to every injector. The fuel pump relay is on the passenger side so I don't see how the green wire would connect to it.

This is the only other wire that is not connected to anything..

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[RonD]

Oops, I saw 1995 in your info, then reread and saw the 1988

So yes, fuel pump relay(EEC relay and WOT relay) is on the passenger side, my bad

If fuel pump is coming on, and there is 12v at the injectors then I would test if you have pressure at the rail, the schrader valve is like a tire valve, center pin releases pressure, but BE CAREFUL, 30psi should be in there and gas can spray a long ways, use a towel over your hands to block it, or even better a pressure tester

Only other thing is the Ground from the computer to open the injectors.
The '88 should be Batch Fire, this means on a 4cyl 2 injectors open at the same time, so there are only 2 Ground wire running back to computer.

Should be a Tan and a White wire, look on the injectors, see if you can trace them back to the firewall.
But they should be part of the main sensor harness that runs to the computer, so no connector in the engine compartment.

Just to ask, does the CEL come on when key is turn on?
So computer is getting power

Did you change the computer for the older engine?
Just wondering because the CKP(crank position) sensor is what told the newer engine when crank was turning so computer would then start spark and fuel injectors.
I think on the older engine that was done by the distributor module, but not sure 100% on the 2.3l.

And I assume if you spray gas/starting fluid into the intake engine does start but dies so you know fuel is the issue.

 

[eduardo95]

The CEL does come on. I have yet to try the starting fluid. I will double check the ground on the computer later on today or tomorrow morning and try the starting fluid.


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[Road Angels]

How many times have you cycled the key to prime the system, At least a dozen times I hope to refill every thing if the truck sat for a long time, if its been to long the inside of the filter may be nothing but gum and plugged, or the screen may be gummed up,if you can hear the pump then its stopping some where before the fuel rail, I dont remember if the 88 has a transfer pump as well as pressure pump on the frame rail mid cab? what side of the truck is the plug your showing, I can check my 86 2.3

 

[eduardo95]

The plug on the picture is on the driver side.


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[Road Angels]

On mine the one in your had goes no where just hangs, the other one just hangs but its a one wire connector, dont forget the 2.3 and 2.9 uses the same harness, for 88, so there will be left over connectors for things like a/c and such if you dont have it, I have about five unused connectors, if they look all nasty inside with corrosion then more than likely are not used, the other on in the second photo I cant see what color the wires are, Are you sure there isnt a harness that is coming up from under the truck that is hanging or you tucked up out of the way under the truck, for back up switchs and such