First gen blues. 87 2.9

[RonD]

Yes, 50/50 test just to make sure spark is working AND..........sparking at the right time

You can manually turn on the fuel pump relay on OBD1 vehicles

You need to find the OBD1 connector in the engine bay, in 1987 it should be on passenger side of the engine bay between fuse box and firewall on the main wiring harness to the computer in the cab, it may have a cap on it that says "EEC"

Look here for OBD1 plug slots: https://www.therangerstation.com/tech_library/OBD_I.shtml

Fuel Pump slot is labelled
This slot is connected to computer pin 22 and the Ground for the Fuel Pump Relay, the computer grounds the fuel pump relay to activate it with Key on, but only for 2 seconds, its a safety thing
So you can use a jumper wire in that slot to Ground the fuel pump relay full time
Ground a jumper wire
Turn on the key
Put jumper wire in that slot, you should hear fuel pump relay "click" if its working, and you should hear the fuel pump come on if its working

You can try to start the engine, IF you hear the fuel pump running
If it starts and runs then try pulling out the jumper, if engine runs for a few seconds and stalls then YES, you may have a computer problem
But put the jumper back and restart, then go for a drive and see if there are any other engine issues

If there is no "click" of fuel pump relay with key ON and Jumper in place:
You can also use a volt meter and test that same slot for 12volts with key on, it should show 12v because fuel pump relay gets 12v with key on, so you are seeing voltage passing thru the fuel pump relays coil
If no 12v then EEC relay or its wire to fuel pump relay is bad

The fuel pump power is from a fusible link connected to starter relays(solenoid) battery positive post
There will be a few fusible links on that one post, that post is the Power Distribution Point for the whole vehicle

So if fuel pump doesn't come on when fuel pump relay is activated then either the pump is bad or fusible link is blown
When you have the Ground jumper in place, and Fuel pump relay "clicks", use volt meter at the inertia switch to test if there is 12volts from the fusible link



Overall its more likely you would burn out fuses and fusible links than damage the computer by bad battery "jumping"
You can also damage alternator's voltage regulator
So once you do get engine running you should test for that

 

[alwaysFlOoReD]

Thanks @RonD
Every time I read one of your answers I learn something.

 

[rusty ol ranger]

Im just wondering if he fried the TFI.

IIRC the TFI has something to do with fuel pump operation...and thats exactly how rusty 1.0's tfi died.

 

[franklin2]

Im just wondering if he fried the TFI.

IIRC the TFI has something to do with fuel pump operation...and thats exactly how rusty 1.0's tfi died.

Looking at the last few posts, he said he has spark. So that would mean the TFI is working. And the TFI will make spark at base timing even if the computer is burnt out. So it's still up in the air what is actually wrong. It may indeed be the computer, but more testing needs to be done.

 

[rusty ol ranger]

Looking at the last few posts, he said he has spark. So that would mean the TFI is working. And the TFI will make spark at base timing even if the computer is burnt out. So it's still up in the air what is actually wrong. It may indeed be the computer, but more testing needs to be done.

TFI's have so many failure modes i dont rule anything out.

Not saying thats it...but,..

 

[franklin2]

Here's a older ranger diagram I found. I highlighted some of the important power wires with colors. You know he should be getting at least one click from the main ECM relay. Problem is, I can't remember where it's located. I know there is one on the pass side inner fender, but I don't know if that is the fuel pump or the main ECM relay. Anyway, the computer has nothing to do with the main ECM relay, that comes from the ignition switch.

Older ranger diagram with highlights by D Franklin, on Flickr

 

[rebel ranger]

50/50 test;
Will it fire up if you spray fuel into the throttle body? If so then its fuel related. If not then electrical.
There is a green relay on the passenger side fender. It sends power to the fuel pumps. Check that. Also the brown one is the ecm relay and if its pooched no power gets to the green one.

Yes, that's the first thing I did, it will fire up with a shot of fuel. I replaced the two relays with two off my '88 2.3 Ranger, still no relay click. That's not to say those two relays off the '88 are working because it has been a while since that truck has been run. Would the ECU out of the '88 work in the '87?

 

[gaz]

I would focus on whether you have:

Fuel issue
Gravity cut out activated
Fuel pump fail

I've never had a fuel pump that petered out, it was always worked one minute then just dead.

If the fuel is good, back to a possibly WEAK or intermittent ignition (spark). #1 culprit if that's the case is ignition module (TFI). A weak or intermittent weak spark will fire, run a little but want to die.

Is this a manual or auto tranny?

 

[PetroleumJunkie412]

Yes, 50/50 test just to make sure spark is working AND..........sparking at the right time

You can manually turn on the fuel pump relay on OBD1 vehicles

You need to find the OBD1 connector in the engine bay, in 1987 it should be on passenger side of the engine bay between fuse box and firewall on the main wiring harness to the computer in the cab, it may have a cap on it that says "EEC"

Look here for OBD1 plug slots: https://www.therangerstation.com/tech_library/OBD_I.shtml

Fuel Pump slot is labelled
This slot is connected to computer pin 22 and the Ground for the Fuel Pump Relay, the computer grounds the fuel pump relay to activate it with Key on, but only for 2 seconds, its a safety thing
So you can use a jumper wire in that slot to Ground the fuel pump relay full time
Ground a jumper wire
Turn on the key
Put jumper wire in that slot, you should hear fuel pump relay "click" if its working, and you should hear the fuel pump come on if its working

You can try to start the engine, IF you hear the fuel pump running
If it starts and runs then try pulling out the jumper, if engine runs for a few seconds and stalls then YES, you may have a computer problem
But put the jumper back and restart, then go for a drive and see if there are any other engine issues

If there is no "click" of fuel pump relay with key ON and Jumper in place:
You can also use a volt meter and test that same slot for 12volts with key on, it should show 12v because fuel pump relay gets 12v with key on, so you are seeing voltage passing thru the fuel pump relays coil
If no 12v then EEC relay or its wire to fuel pump relay is bad

The fuel pump power is from a fusible link connected to starter relays(solenoid) battery positive post
There will be a few fusible links on that one post, that post is the Power Distribution Point for the whole vehicle

So if fuel pump doesn't come on when fuel pump relay is activated then either the pump is bad or fusible link is blown
When you have the Ground jumper in place, and Fuel pump relay "clicks", use volt meter at the inertia switch to test if there is 12volts from the fusible link



Overall its more likely you would burn out fuses and fusible links than damage the computer by bad battery "jumping"
You can also damage alternator's voltage regulator
So once you do get engine running you should test for that

Adopt me.

 

[rebel ranger]

Yes, 50/50 test just to make sure spark is working AND..........sparking at the right time

You can manually turn on the fuel pump relay on OBD1 vehicles

You need to find the OBD1 connector in the engine bay, in 1987 it should be on passenger side of the engine bay between fuse box and firewall on the main wiring harness to the computer in the cab, it may have a cap on it that says "EEC"

Look here for OBD1 plug slots: https://www.therangerstation.com/tech_library/OBD_I.shtml

Fuel Pump slot is labelled
This slot is connected to computer pin 22 and the Ground for the Fuel Pump Relay, the computer grounds the fuel pump relay to activate it with Key on, but only for 2 seconds, its a safety thing
So you can use a jumper wire in that slot to Ground the fuel pump relay full time
Ground a jumper wire
Turn on the key
Put jumper wire in that slot, you should hear fuel pump relay "click" if its working, and you should hear the fuel pump come on if its working

You can try to start the engine, IF you hear the fuel pump running
If it starts and runs then try pulling out the jumper, if engine runs for a few seconds and stalls then YES, you may have a computer problem
But put the jumper back and restart, then go for a drive and see if there are any other engine issues

If there is no "click" of fuel pump relay with key ON and Jumper in place:
You can also use a volt meter and test that same slot for 12volts with key on, it should show 12v because fuel pump relay gets 12v with key on, so you are seeing voltage passing thru the fuel pump relays coil
If no 12v then EEC relay or its wire to fuel pump relay is bad

The fuel pump power is from a fusible link connected to starter relays(solenoid) battery positive post
There will be a few fusible links on that one post, that post is the Power Distribution Point for the whole vehicle

So if fuel pump doesn't come on when fuel pump relay is activated then either the pump is bad or fusible link is blown
When you have the Ground jumper in place, and Fuel pump relay "clicks", use volt meter at the inertia switch to test if there is 12volts from the fusible link



Overall its more likely you would burn out fuses and fusible links than damage the computer by bad battery "jumping"
You can also damage alternator's voltage regulator
So once you do get engine running you should test for that

Yessir, thanks for the reply. I checked fusible links before, getting battery voltage on both sides of links, and voltage to the relay(yellow wire) plug. The ground was something I had forgotten, as I went through something similar with my '88 years and years ago. Getting older and forgetting all the fun stuff with these Rangers. I jumped the test plug to ground and both relays clicked, pump came on, engine started and ran like it always did.
Now, for the $64 question. Would the EEC out of the '88 2.3 truck work in the '87 2.9 truck? Or, what is it going to hurt if I just ground that plug and ride like the wind?
I know the truck won't shut off with the inertia switch bypassed in the event of a rollover, or a good crash. What's the risk of running it like this with the test plug jumped to ground?

 

[rebel ranger]

I would focus on whether you have:

Fuel issue
Gravity cut out activated
Fuel pump fail

I've never had a fuel pump that petered out, it was always worked one minute then just dead.

If the fuel is good, back to a possibly WEAK or intermittent ignition (spark). #1 culprit if that's the case is ignition module (TFI). A weak or intermittent weak spark will fire, run a little but want to die.

Is this a manual or auto tranny?

Thanks for the reply. Check above post, it fires up and runs like it always did with the test plug grounded.
It's manual.

 

[gaz]

I would not expect the 2.3 PCM to run a 2.9.

If you know it's the gravity switch just replace it. I've never driven without one but I suppose for an emergency or to drive to the parts store to pick one up.

 

[rebel ranger]

I would not expect the 2.3 PCM to run a 2.9.

If you know it's the gravity switch just replace it. I've never driven without one but I suppose for an emergency or to drive to the parts store to pick one up.

It's not the gravity switch. It's the EEC not grounding the fuel pump relay.
I see several other Ford EECs that have a long list of vehicles that they will operate with 2.3, up to V8s. I have not experienced it personally, but I have seen the listings.

 

[PetroleumJunkie412]

Read and meditate on this. Achieve zen.

Nearly all 80s ford computers have the same binary files (software) that runs ignition advance and fueling. It's sometimes a matter of sensors and pinout, or chipsets (read: stooooooopid primitive) that change a few parameters.

I tend to beat up on them as crap because they cannot relearn volumetric efficiency, but, they do run for 30 years on primitive crap components in pretty much the worst environment imaginable. Imagine how you'd look after 30 years in the floor well of a ranger.

YOU SALUTE THAT LITTLE COMPUTER, SIR!

 

[rebel ranger]

Read and meditate on this. Achieve zen.

Nearly all 80s ford computers have the same binary files (software) that runs ignition advance and fueling. It's sometimes a matter of sensors and pinout, or chipsets (read: stooooooopid primitive) that change a few parameters.

I tend to beat up on them as crap because they cannot relearn volumetric efficiency, but, they do run for 30 years on primitive crap components in pretty much the worst environment imaginable. Imagine how you'd look after 30 years in the floor well of a ranger.

YOU SALUTE THAT LITTLE COMPUTER, SIR!

You are RIGHT, bruddah!! I sure hated to see this one bite the dust when I have been jump starting off of it for the last 20 years. And yep, the cables were on the right posts. Just one of those things I reckon.