Guide me on searching for a PCM

[Denisefwd93]

Looking for one for a manual truck. Which other trucks would have the same one/type that will work in my 93 that will be swapped over to manual in the spring? get mine "flashed" ? or just look for one from salvage?
Thanks!

 

[stmitch]

It will need to match your current engine, and your desired trans. So, if you currently have a 4.0/auto it will need to be from a 4.0/Manual.

 

[RonD]

yes, ^^^

But needs to match engine specifics as well:
With or without EGR
With or without Cam position sensor

Are the two I can think of

My '94 4.0l has neither of the above, if I got a PCM that was for a 4.0l with EGR then I would get a CEL all the time because there is no feedback from EGR sensor, same for CPS

 

[Denisefwd93]

Well, my 4.0 doesn't have an egr, Don't know about the CPS will check into that I think it doesn't However

 

[adsm08]

In 1993 for the 4.0 EGR and CPS are pretty much the defining features of the California Emissions package. As far as I have been able to figure if you have one you have the other.

Check ebay. That's where I have been getting mine.

 

[Denisefwd93]

In 1993 for the 4.0 EGR and CPS are pretty much the defining features of the California Emissions package. As far as I have been able to figure if you have one you have the other.

Check ebay. That's where I have been getting mine.

I have looked, seems kinda of rare what my truck needs. Should I just plan getting another from any compatible year make and have it "flashed" ? I can get it done locally or find out what a ford dealer would charge.

 

[adsm08]

EEC-IV computers cannot be reprogrammed.

 

[Denisefwd93]

EEC-IV computers cannot be reprogrammed.

I take that to mean the one in my truck and the one I'm searching for?

 

[adsm08]

Yes.

 

[Andy D]

You cant run a 5spd ranger with the ECU from an automatic?. The pack rat in me has wanted a spare ECU for the Rat. Its a 49 state truck,non EGR. What will fit?

 

[Denisefwd93]

You cant run a 5spd ranger with the ECU from an automatic?. The pack rat in me has wanted a spare ECU for the Rat. Its a 49 state truck,non EGR. What will fit?

I've read a few swap overs that did run with a auto programmed ECU but they had problems with CELs. I'm planning on doing this as close to stock as possible. If I have to buy one I will.

ASM I need numbers or photo of the ECM stickers and or door sticker to find the right one?

 

[RonD]

You "can" run an automatic ECU in a manual vehicle, but you will have the CEL on all the time because there are no hook ups for the torque converter lockup or 3/4 shift solenoid, so computer thinks there is a problem.

Idle will also be high, 750-800, because that is the programmed idle for automatics.


Any PCM from 1990-1994 Ranger 4.0l from 49 states(federal) with manual trans should work.


Mid-'80s Rangers with Fuel injection got the EEC-IV computer(OBD I), it was used in Rangers until 1994
In 1995 Rangers all got the EEC-V(OBD II) computers, these were used until end of production.


Ford doesn't publish software version cross references.

Part number for ALL PCMs is 12A650
Then there is a pre-number for year and vehicle model, and a post-number for software version
So if you have this: F17F-12A650-GA
F = 199, E =198
1 = 1 so F1 = 1991 model year, F2 would be 1992, F3 = 1993, E9 would be.............1989
7 = Ranger, Z here = mustang
F = Engine part

12A650 = Ford part number

GA = revision

There will also be a 3 or 4 digit number on the label in larger print, stamped on, that has the details of automatic, manual, EGR, CPS, and engine size, these are the numbers Ford should but never did publish.

Good read here on some EEC-IV numbers: http://oldfuelinjection.packrad.net/page17.html

Actually a good site all around to bookmark

 

[Denisefwd93]

Ron that helps a lot thank you! Other questions: EGR, CPS Are not present in my truck is that a problem?And I think I can surmise the newer PCMs can't be retrofitted to the older Correct?

 

[adsm08]

The 4.0 gets dicey mixing and matching computers and harnesses around your year.

If it came with CPS you need a CPS PCM or it will run poorly or not at all. Same with no cam sensor. The reason is the cam sensor was used on sequential fire injection systems to determine which cylinder was where. No cam sensor means batch fire, so 3 injectors fire at the same time.

The differences in strategies require differences in wiring.

Honestly, you should be able to run an 4.0 manual computer back to 1990 without issue.

 

[Denisefwd93]

Thank you gentlemen all! going to start my search based on this very good information! Got the pedal assembly yesterday! Thank you David!