2.3L ('83-'97) 1986 Ranger 2.3L FI issues.. pls help

[gward]

Hi everyone, i just purchased my first ever 1986 Ford Ranger. Has a FI 2.3L 4 banger with a 5spd manual trans.

Took 2 days to figure out the PO's wiring mess but i have now got it to crank and start on carb cleaner.

My main question is, the fuel pump relay connector is showing +12 volts on 3 wires (2 relay operation terminals and 1 of the pump out wires) the other is a ground.

How on earth is that supposed to make the relay work if both terminals that are supposed to activate the relay are +12v?

I'm pretty sure the injectors are clogged solid, if i jump the relay out the pump on the frame rail runs (cant hear the in tank one if it even has one anymore) but it wont start.

Thanks in advance,
Gordon

 

[RonD]

Fuel pump relay, green base, is grounded/activated by the engine computer, but ONLY for 2 seconds with key on, its a safety thing
Once engine starts, RPMs above 400, computer will ground fuel pump relay full time

Easier way to test fuel pump relay is to find the OBD1 connector in engine bay, its on main wiring harness, originally clipped to engine bay fuse box

Look at the first 2 drawings here: https://www.therangerstation.com/tech/testing-eec-iv-equipped-engines/

In the 2nd drawing the Fuel Pump Relay slot is labelled, that slot is the Ground wire from computer to fuel pump relay
If YOU ground that slot then with key on the fuel pump relay will activate and pump will run full time, as long as key is on, good for testing and even driving if you want

wiring diagram here: https://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_ElectronicEngControls2_3_1of3.JPG

Fuel pump fuse feeds 12v full time to relay, black/yellow wire
When relay is activate that 12v goes out to inertia switch in cab, on the Green/yellow wire

The activation coil gets 12v with key on from EEC relay, on red wire
The computer grounds the other end of coil using the blue/orange wire<<<<this wire also goes to VIP test connector, another name for OBD1 test port

A relay's coil is just a wire wrapped around a metal core, so if one end of the wire has 12v the other end also shows 12v, until its grounded
In this case by YOU or the computer

Yes, there were 2 fuel pumps from 1986 thru 1988 on EFI Rangers, one in the tank and one in the frame rail, they share the one 12volt wire from inertia switch, pink/black wire


Simple test, install jumper to activate fuel pumps full time
Crank engine over a few times
Pull out any spark plug
See if tip is WET
If it is try to light it with a match or lighter, if it doesn't burn then its NOT fuel you are pumping into the engine

If tip is not wet then injectors are clogged

 

[gward]

Hi RonD, thanks for the info. I jumped it and both pumps come on, gauge says 42psi at the rail... however the plugs are dry. Looks like im pulling injectors tomorrow lol.

I replaced the original fuel pump relay plug and relay itself with an aftermarket type. Still wont turn the pumps on with the key. I may just bypass the silly thing so they run full time with the key on.

 

[gward]

Oh and someone has already bypassed that inertia switch aka wires soldered together.

 

[SenorNoob]

It sounds to me like the computer isn't telling the pump or injectors to run.

Have you got all of the power and grounds it needs? Do you have a noid light to check to for injector pulse? Any other way to check if the computer is working? Oh, does the check engine light work?

 

[RonD]

+1 ^^^

Injectors may be fine, computer may be the issue
I don't think 1986 had a CEL(check engine light)?

On the upper intake is the IAC Valve, unplug its 2 wires
Connect volt meter to the 2 wires, red wire has 12v with key on, other wire goes to computer, computer grounds it to open IAC valve for start up, so you should see 10-11volts with key on
If not computer is not booted up which is why no injectors, and no fuel pump relay trigger

Spark system is separate, which is why it starts by manually adding fuel, 50/50 test

Pull computer and open it up have a look inside, there are 2 or 3 radial capacitors that can leak and/of fail, cheap to replace

On the link I posted above for OBD1 port you can follow the diagram for hooking up volt meter to test computer for codes, this would also tell you if computer was "on"


1986 may have an EMISS light, emissions light, no connection to CEL/MIL lights, it would do a bulb test with key on and then come on full time after 60k miles or so to tell owner to bring vehicle in to Ford for testing emissions systems, then it was reset for another 60k miles

 

[gward]

It sounds to me like the computer isn't telling the pump or injectors to run.

Have you got all of the power and grounds it needs? Do you have a noid light to check to for injector pulse? Any other way to check if the computer is working? Oh, does the check engine light work?

I keep finding broken wires and repairing as i go, figured i would check the ignition switch next.
I dont have noid lights and i havent seen any dash light to be honest.

 

[gward]

RonD,

I will give that a try, this poor truck has been sitting for 2-3yrs.

 

[gward]

Okay so the IAC is located on the air box i found out, tested at that plug and get 12 volts (ish) with the key on.

Found a broken green wire going into the coil (no idea how it had spark with that broken wire) and fixed that.

Checked the ignition on the column and the switch is falling apart, even holding and wiggling doesnt engage the fuel pump.

I will try and pull "codes" from it after lunch.

So much for an easy fix and drive it haha.

 

[gward]

Tried pulling codes and all i get is a solid test light, no blinks at all.

 

[gward]

I got to looking at this intake, looks like it would be pretty easy to adapt a 2bbl carb to it.

Being as it already has spark and will run on ether.. would it need anything other then a low pressure fuel pump?

Thx

 

[RonD]

No

You wouldn't have spark advance
You would have to find and use a vacuum advance distributor and spark system

2.3l was first used in 1974 Pinto and thru 1980 or so, used a Duraspark system with vacuum advance, you would use an HEI spark module with it, not the Duraspark module

 

[gward]

Thus far ive had no luck finding a distributor or suitable carb.

Not sure i want to buy another ecu for $200, im thinking this truck has many more issues waiting for me yet.

 

[scotts90ranger]

Oof, figuring out how people butcher wiring is hard, don't envy you...

If it helps at all but I imagine you know this already but on relays pin 85 is usually (I say usually because it doesn't matter with a resistor style relay but some relays have a diode across the control circuit and those DO matter) the ground side of control, 86 is power side of control and 30 and 87 are the input and outputs (if 5 pin 87A is normally closed, 87 normally open). You can get tricked with a digital volt meter on 85 and 86 but a test light should make it easier (can put the volt meter across the test light too to tell somewhat more).

I'm so glad my '97 just had a bent I beam when I picked it up for cheap, turns out it did have some type of security system at some point but I was able to bypass that easy enough.... didn't find out until I went to put a tach cluster in it...

 

[gward]

I can get the pumps to run and make fuel pressure, really good spark on all 4 but the damn injectors wont activate.

I'm really not sure how to even test the ecu to see if its outputting anything to them. For all i know, theres 10 more broken wires somewhere hahaha.

i did find a used ecu on ebay for under $100 so i may try that as well as a new ignition switch.