story:
bought a 92 ranger less than a year ago
truck would cut off after a few miles
truck came with another computer
computer worked better than the other but it would trigger the check engine light
put the truck on a diagnostics computer...it showed that the computer is not a 4.0 computer mostlikely a 2.9 was looking for a certain sensor that the 4.0 doesnt have reason for check light
bought a 4.0 computer from cardone...turned in the computer that stopped working..this computer was painted black so I couldnt see any markings
the cardone computer worked flawless for 2 weeks then shut off while driving and never started back up
contacted cardone they want to know what computer came in the truck stock
so my question is what computers came in the ranger...and specifically the 1992 5spd 4x4 4.0 extended cab think it is an xlt

 

Welcome to the forum

4x4 or 2WD doesn't matter in 1992 as far as computer is concerned, just FYI

Part number would be F27F-12A650

F2 = 1992, F3 would be 1993, F4 = 1994
7F = Ranger
12A650 = Ford engine computer part number from 1985 to present day

But what you(and they) want is the 2 to 4 digit code that comes AFTER the above part number and that was only found on the label of the ECU you sent back
It would denote engine size, manual or automatic, and EGR or no EGR
Ford never published a cross reference for these numbers, and they are different for each year, i.e. a "1CB" code in 1992 wouldn't mean the same thing in 1991 or 1993
People often call these "calibration codes" although they are actually "revision" codes

You may still have the Software sticker, a white sticker locate near the ECU, it will have a 3 or 4 digit number that tells what software was loaded on to the computer at the factory during assembly, it might help them ID your version
This number is the calibration code, latest software at the time of assembly.

Here is a picture of 3 EEC-IV labels: http://www.autoanatomy.com/ford/catchcodes02.jpg
These are E8 and E9, so 1988 and 1989
And you can see the 2 to 4 digital "revision codes" at the end of the part number, after the 12A650, this is what Cardon would like to have.
Circled is the software codes, this code would also be by itself on a white sticker

If ECU is in engine bay, behind drivers side inner fender, then look just above where it is on inner fender or flat area where hood would sit when closed

You can also Google: F27F-12A650

And see if you can find a match for 4.0l MT(manual trans) and get the revision number from that one
Same number was used in Explorers but they usually had automatics



If computer ran fine for 2 weeks I would think you have another problem, not the computer, for why it won't start.
1992 is 26 years old, so...........fuel pumps quit, ignition switch and relays as well.

 

I appreciate the welcome

"If computer ran fine for 2 weeks I would think you have another problem, not the computer, for why it won't start.
1992 is 26 years old, so...........fuel pumps quit, ignition switch and relays as well."

so this can be fact even if the computer that throws a code will work (will drive a hundred miles)

yet I just remembered with this computer (the code thrower) it will run good when warmed up but at first crack in the morning when I start the truck if I get out and grab something then come back it will shut off..any ideas (test I can run)


oh yeah what was going on with Ford's ranger design. I know everyone knows about the firewall drop off cubby...ie where rust forms and will eat the body and cause water to run where the cpu is!

 

All gasoline engines need to be "Choked" when cold, that means Rich Fuel mix, high idle and advanced spark timing.

With fuel injection a Choke Plate can't be used like on a carb engine.

So computer has an engine temp sensor, the ECT(engine coolant temp) sensor, that tells it when to Choke the engine, when engine coolant is under 150degF

If this sensor is telling computer engine is always "warmed up" then engine will run rough and stall when cold, but run fine after warmeup

ECT sensor has 2 wires and should be near thermostat housing.

There is also a Temp SENDER, 1 wire, it is used for dash board temp gauge only, they are near each other but NOT interchangeable

 

how would I test these sensors

 

You can use a volt meter and sewing needle to test ECT sensor

Engine cold and off, key on
Set meter to DC Volts
Insert needle into one of the wires on the ECT sensor
Put black probe of meter on a Ground
Touch Red Probe to needle
Should read 5volts or 3volts
If 5volts remove needle and put it in the other wire, 5v is the power wire, it is always 5v
Other wire is the Temp voltage, about 2v-3v cold

Leave needle in place, start engine
Let it warm up for a few minutes
Turn off engine, key on
retest voltage should be lower than before, at full warm up, under 1 volt
If voltage was already low and is not changing much then replace sensor

The SENDER has nothing to do with engine operation, it is only connected to dash temp gauge, you don't test these just replace them if dash temp gauge doesn't work

 

RF Vet
will test this out in as soon as possible and get back to this post: need to pick up a voltmeter.
also side note
on the 92 ranger did the t case motor have a bracket

 

Bracket?

They did come with a "bracket" on the end of the shift motor, pictures here: https://www.explorerforum.com/forums...-motor.123542/

But people often left it off if they replaced motor, or serviced it, never read about any issues if it was not there

 

ok,
going to test the ect sensor tomorrow
picked up a obd i/ii scanner from amazon (haven't made it yet)

does the 92 ranger have a eec power relay
if so does this problem sound like an eec power relay
how to test? (found a how to test a eec power relay for the 5.8, 5.0, 4.9)?

 

EEC Relay is there in the engine fuse box, some times under the fuse box, along with EEC fuse

When you turn on the key the EEC Power relay closes and sends 12volts to...........EEC(computer), fuel injectors, fuel pump relay(not fuel pump), coil pack, EDIS spark module, MAF heater, IAC Valve, EVAP system, and transmission if automatic.

So if EEC relay, or EEC fuse, had a problem then engine could not start, and yes it could just shut off while driving if this relay opened, cutting 12volts to all the engine systems

 

Ok
got my multimeter, picked up some t shaped pins.

on my truck 92 ford ranger with the v6 4.0 engine the ect sensor is immediate to the right of the thermostat housing


1. Tested multimeter with battery poles (12plus volts)
2. Had to stick the t shaped pins in good to get them to stick into the wire (ps to be on the safe side what do you recommend to cover the puncture of the wire)
​​​​​​3. Used the main engine ground for the test

results:
Light green with Red strips 0.33 (multimeter on 9v) with key on I let the engine warm up to operating temp 0.23

White with red strips on 0.05 (multimeter on 9v) with key on...let it run got .09

Light Green with red strip must be command
White with red strip must be power

So how this looks at the moment I have a bad power

 

Picked up a ECT sensor fromO
I did the unprofessional and just replaced the sensor after I tried the test posted a few sets back
when I was at the auto parts store I asked what test I could do/also stopped by a young mechanic and did the same
Lance from O said do the ohms/temp test
Aliika the mechanic said trick the computer with a resistor on the ECT sensor circuit
I'm thinking the ohms test would be the best out of the 2

replacing the ect sensor with a new:
took off the rubber intake boot, gotta long 1in wrench turned the sensor in a favorable angle to position the clips, got 3 small flat head driver and slide the clips, carefully spun the sensor out, put the new 1 on then
Crunk the truck from a cold start. It was sitting a few days. Ran good...stopped once after; it idled and ran for 10 mins straight
this was done with the cpu that is not for the truck..


going to try my new cpu....see if it cranks and starts...like I stated before the new cpu ran good for a week or 2..put bout 300 miles on it then 1 day it stopped (engine wasnt warmed up and I was driving) it hasn't started since with that cpu...
yet the used cpu would start it and I have been running with it ever since