Expy to Nav ECC interchangable???

[shaggymane]

A local out of the way bone yard where parts are cheap just got a 91 4dr Exp AT, AC 4x4. I have a 91 Navajo.

I thought it would be a good idea to grab some spare parts. One of them being the computer, the ECC.
Would they interchange? The Expy tranny is mechanical/hydraulic so seems to me that shouldn't be a problem.

However, O R's lists 11 different part numbers for both the Nav and the Expy and then also add things like "With ID Number F17F-12A650-ZA"

Is That a reference to the vin number?


eta neither vehicle is a Cal vehicle

 

[shaggymane]

bumping this thread because i still think someone knows

 

[MrShorty]

Usually when you replace the PCM, you try to match those numbers so the calibrations all match up.

As far as I know (ignoring transmission differences), engine management is basically the same on all '91 4.0's. The only difference is internal calibrations inside the PCM's programming. Except for differences between auto/manual transmission, the PCM's should interchange ok.

 

[93F-Explorer]

I have a 93 and the computer code for Oreillys is F37F-ZB

Found a 94 Ex sport same everything and its a F47F-NB

I "Ass"ume that the first number is the year of the vehicle... Since you stated the F17F is from a 91 that assumption holds water... I am still trying to figure out what the first letter in the ZB or NB means...

I am putting the 94 NB in place of my 93 ZB tonight... Will let you know

 

[shaggymane]

Usually when you replace the PCM, you try to match those numbers so the calibrations all match up.

As far as I know (ignoring transmission differences), engine management is basically the same on all '91 4.0's. The only difference is internal calibrations inside the PCM's programming. Except for differences between auto/manual transmission, the PCM's should interchange ok.

So it's basically a go. Curious what variations on the internal calibrations might be. Would a heavier vehicle (4dr) with a tow package have a longer pulse width on the injectors for more power? anything like that?

*****

93F-Explorer, How'd ya make out?

 

[93F-Explorer]

Just to inform you the 94 did not work in my 93...

93 is batch fire and 94 is sequential fire... so I didnt have any luck =(

 

[MrShorty]

Just to inform you the 94 did not work in my 93...

93 is batch fire and 94 is sequential fire... so I didnt have any luck =(

That's the tough part about swapping PCM's to a '93. Some '93's are batch fire and some are SEFI.